feat: entry previews (#24)

* feat: entry previews (video, tweet, article, iframe, image, audio bar)

- Add PreviewPanel dispatch hub routing by entity_kind + artifact extension
- VideoPreview: HTML5 <video> for YouTube/Instagram/TikTok/Reddit/X posts
- TweetPreview: tweet card, thread, and X article renderer (ported from x-article-renderer)
- IframePreview: sandboxed iframe for SingleFile web pages and PDFs
- ImagePreview: image viewer with click-to-open-fullsize
- AudioBar: persistent fixed-bottom player (Spotify-style) that survives entry navigation
- Lift entryDetail to App.jsx, shared between PreviewPanel and ContextRail
- 3-column layout (workspace | 300px preview | 340px rail) when preview active
- Stale-guard fixes: seq incremented before early returns in all async effects
- handleRearchive: capture startSeq/entryUid at call time, guard every async resume
- TweetPreview: reset loading/error/tweets before early-return branches

* feat: entry previews — tweet/thread/article/video/audio/image/iframe/pdf

- PreviewModal: modal overlay with new-tab link (↗) and keyboard close
- PreviewPanel: routes by entity_kind + primary_media extension to the
  correct viewer (tweet/video/audio/pdf/html/image/fallback)
- TweetPreview: full X-style tweet, thread, and article renderer with
  local artifact map for archived media (CDN fallback)
- AudioBar: persistent fixed bottom player, triggered via ContextRail
  Play button; body.has-audio-bar pads content above it
- VideoPreview, IframePreview, ImagePreview: inline viewers
- PreviewPage: standalone /preview/:archiveId/:entryUid route
- ContextRail: Play/Preview buttons; isAudio/isPreviewable detection
- App.jsx: preview modal state, currentAudio state, preview route guard,
  has-audio-bar body class effect
- routes.rs: CSP updated (media-src self blob https; frame-ancestors self;
  Google Fonts + external images/scripts whitelisted)
- styles.css: preview modal, tweet-wrap scroll (min-height:0), audio bar
  body padding, newtab button, preview panel flex layout

* style: tighten article/tweet preview spacing

- aMeta padding: 14px → 10px
- article title marginBottom: 10px → 8px
- aAuthorRow marginBottom: 10px → 8px
- bH1 top margin: 20px → 16px
- bH2 top margin: 18px → 14px
- bHr margin: 20px → 14px
- .preview-tweet-wrap padding: 20px → 12px (already committed)

More content visible above the fold in both modal and standalone views.

* feat: tweet/article preview quality pass

HTML entities: decode &gt; &lt; &amp; etc. on sliced segments only
(entity offsets index the stored string; decoding before slicing shifts them)

Image lightbox: click any tweet/thread/article image to open full-screen
viewer; cmd+click follows <a> to open in new tab; arrow-key + ‹ › nav;
Escape closes; 1/N counter; ↗ open-in-new-tab link

Multi-image grid: 2 photos → side-by-side (180px rows); 3 → left spans
both rows; 4 → 2×2 (140px rows); single image unchanged

Empty media grid ghost: build photos/videoItems arrays first, render
.mediaGrid div only when at least one item resolved (advisory: never gate
on raw media.length when map items can all return null)

QT indicator: ↻ QT badge on tweet.is_quote_status === true entries

Modal shrinks for short content: height: 88vh → max-height: 88vh;
.preview-modal-body gets max-height: calc(88vh - 52px) so long threads
still scroll (advisory: don't rely on flex:1 once parent has no fixed height)

Video scrollbar leak: .preview-modal-body overflow: auto → hidden; each
child (tweet-wrap, video-wrap, iframe) manages its own scroll surface

Styled thin scrollbar on .preview-tweet-wrap (matches workspace rail)

ArticleRenderer: cover image and body images are lightbox-clickable;
opts thread through renderBlocksJSX → renderBlockJSX → renderAtomicJSX

* fix: move artifact fetch to api.js; stop Escape propagation from lightbox

- Export fetchEntryArtifacts(archiveId, entryUid, indices) from api.js
  using Promise.all + getJson (follows project convention: all /api calls
  go through api.js, never inline fetch in components)
- TweetPreview: import fetchEntryArtifacts, replace inline Promise.all
- MediaLightbox keydown handler: stopPropagation + preventDefault for
  Escape/ArrowLeft/ArrowRight so the parent PreviewModal window listener
  does not also fire and close the modal behind the lightbox

* fix: iframe/page preview height chain and toolbar UX

Problem: changing .preview-modal from height to max-height broke iframe
previews - <iframe style='flex:1'> needs a concrete ancestor height, which
max-height alone doesn't supply when content is shorter than the cap.

Fix - CSS:
  .preview-modal--full { height: 88vh } applied to non-tweet modals
  .preview-modal--full .preview-modal-body { max-height: none }
  .preview-iframe-toolbar span: remove text-transform/letter-spacing
    (was uppercasing the URL/title in shouty caps)

Fix - PreviewModal: className adds --full when entity_kind is not
  tweet/tweet_thread; tweet previews keep shrink-to-fit behavior.

Fix - PreviewPanel: pass title + original_url from summary to IframePreview
  for both HTML and PDF; wrappers use flex:1/minHeight:0 not height:100%.

Fix - IframePreview:
  - Accept title + originalUrl props; show originalUrl in toolbar (falls
    back to artifact src only when original_url absent); show title above
    URL when available
  - flex:1 + minHeight:0 instead of height:100% on the wrap div
  - Single unified layout for page + pdf (both just show the iframe)

* feat: expand t.co links; linkify bare URLs in tweet and article text

Frontend:
- resolveEntityBounds: try multiple candidate strings in order (u.url
  first, since that's the t.co short URL that appears in full_text)
- normalizeUrlAnn: multi-candidate search; href = expanded > url,
  display = display_url > expanded > url
- linkifyText(): regex linkifier for entity-less bare URLs; trims
  trailing punctuation [.,;:!?)] before linking; used in both
  renderTweetTextJSX and renderInlineJSX including their early-return
  paths (anns.length === 0) that previously bypassed linkification
- renderInlineJSX: fix mention href mention.name → screen_name;
  replace t.co segment text with url.display when entity covers it

Scraper (vendor/twitter/scrape_user_tweet_contents.py):
- extract_tweet_data: when note_tweet text is used, pull urls/mentions/
  hashtags/symbols from note_result.entity_set (correct indices for the
  note text); keep media from legacy.entities (no note media downloads)

* feat: server-side t.co resolver + frontend augmentation

Server (routes.rs):
  POST /api/util/resolve-tco — unauthenticated, accepts JSON array of
  https://t.co/<alphanumeric> URLs only (strict regex validation, no SSRF
  via input), capped at 50 per batch, 3 s timeout, redirect(Policy::none)
  so the server only ever touches t.co itself. HEAD first, GET fallback if
  HEAD returns no Location. Location sanitized to http/https only —
  javascript:/data:/etc. fall back to the original t.co.

api.js:
  resolveTcoUrls(urls) — project-convention wrapper for the new endpoint.
  Returns {} on failure (callers degrade gracefully to bare t.co links).

TweetPreview.jsx:
  After tweet data loads, per-tweet range-based coverage detection:
  builds covered [start,end) from existing entity fromIndex/toIndex or
  indices fallback, then finds regex matches whose span is NOT covered.
  Resolves unique uncovered t.co URLs via resolveTcoUrls(), synthesises
  one entity per occurrence (with exact fromIndex/toIndex so normalizeUrlAnn
  gets correct bounds even for duplicate t.co URLs in the same tweet).
  Augments entities.urls before setTweets() so all rendering paths
  see expanded URLs.

* feat: suppress rendered media attachment URLs from tweet text

renderTweetTextJSX now accepts skipSpans=[] as third param.
Skip-span boundaries are added to the pts split set so a trailing
media t.co inside a plain segment still gets isolated and suppressed—
not re-linked by linkifyText. Early return only when both anns and
skipSpans are empty.

TweetCard computes mediaSkipSpans after building photos/videoItems:
for each rawMedia item whose src resolved (photo src match; any video),
resolveEntityBounds(m, ft, m.url) gives the precise [s,e] span using
indices/fromIndex first, indexOf fallback—then the span is passed to
renderTweetTextJSX so the t.co attachment URL is silently dropped.

frontend/src/App.jsx

@@ -1,5 +1,5 @@
 import { useState, useEffect, useCallback, useRef, createContext } from 'react'
-import { fetchArchives, fetchEntries, searchEntries, fetchRuns, fetchTags, checkSetup, fetchMe } from './api'
+import { fetchArchives, fetchEntries, searchEntries, fetchRuns, fetchTags, checkSetup, fetchMe, fetchEntryDetail } from './api'
 import LoginPage from './components/LoginPage.jsx'
 import SetupPage from './components/SetupPage.jsx'
 
@@ -12,11 +12,20 @@ import TagsView from './components/TagsView'
 import CollectionsView from './components/CollectionsView'
 import SettingsView from './components/SettingsView'
 import ContextRail from './components/ContextRail'
+import PreviewModal from './components/PreviewModal'
+import AudioBar from './components/AudioBar'
+import PreviewPage from './components/PreviewPage'
 import { displayPath } from './utils'
 import ToastStack from './components/ToastStack'
 
 export const AuthContext = createContext(null);
 
+// Detect /preview/:archiveId/:entryUid at load time (static — no navigation)
+const PREVIEW_ROUTE = (() => {
+  const m = window.location.pathname.match(/^\/preview\/([^/]+)\/([^/]+)/)
+  return m ? { archiveId: m[1], entryUid: m[2] } : null
+})()
+
 const VIEWS = ['archive','tags','collections','runs','admin','settings']
 const SETTINGS_TABS = ['profile','tokens','instance','storage']
 
@@ -89,8 +98,24 @@ export default function App() {
     () => sessionStorage.getItem('ublockWarningIgnored') === 'true'
   )
 
+
+  // ── Entry detail (shared between PreviewPanel and ContextRail) ──────────
+  const [entryDetail, setEntryDetail] = useState(null)
+  const detailSeqRef = useRef(0)
+
   const humanizeTags = currentUser?.humanize_slugs ?? false;
 
+  // Fetch entry detail whenever selected entry changes
+  useEffect(() => {
+    const seq = ++detailSeqRef.current
+    setEntryDetail(null)
+    if (!selectedEntry || !archiveId) return
+    fetchEntryDetail(archiveId, selectedEntry.entry_uid).then(det => {
+      if (seq !== detailSeqRef.current) return
+      setEntryDetail(det)
+    }).catch(() => {})
+  }, [selectedEntry, archiveId])
+
   // Persist captureDialogOpen to sessionStorage
   useEffect(() => {
     sessionStorage.setItem('captureDialogOpen', captureDialogOpen)
@@ -172,7 +197,9 @@ export default function App() {
   }, [archiveId])
 
   // Sync view + settingsTab → URL
+  // Sync view + settingsTab → URL (skip when serving a standalone preview page)
   useEffect(() => {
+    if (PREVIEW_ROUTE) return
     const path = locationPath(view, settingsTab)
     if (window.location.pathname !== path) {
       history.pushState(null, '', path)
@@ -217,8 +244,22 @@ export default function App() {
     setSelectedEntry(prev =>
       prev && prev.entry_uid === entryUid ? { ...prev, title: newTitle } : prev
     )
+    setEntryDetail(prev =>
+      prev && prev.summary.entry_uid === entryUid
+        ? { ...prev, summary: { ...prev.summary, title: newTitle } }
+        : prev
+    )
   }, [])
 
+  const handleDetailRefresh = useCallback(() => {
+    if (!archiveId || !selectedEntry) return
+    const seq = ++detailSeqRef.current
+    fetchEntryDetail(archiveId, selectedEntry.entry_uid).then(det => {
+      if (seq !== detailSeqRef.current) return
+      setEntryDetail(det)
+    }).catch(() => {})
+  }, [archiveId, selectedEntry])
+
   const handleEntryDeleted = useCallback((entryUid) => {
     setEntries(prev => prev.filter(e => e.entry_uid !== entryUid))
     setSelectedEntry(prev => prev?.entry_uid === entryUid ? null : prev)
@@ -258,10 +299,33 @@ export default function App() {
     setUblockWarningIgnored(true)
     setToasts(prev => prev.filter(t => !(t.type === 'warning' && t.locator)))
   }, [])
+  const [previewEntryUid, setPreviewEntryUid] = useState(null)
+  const [currentAudio, setCurrentAudio] = useState(null)
+
+  const handleOpenPreview = useCallback(() => {
+    if (selectedEntry) setPreviewEntryUid(selectedEntry.entry_uid)
+  }, [selectedEntry])
+  const handleClosePreview = useCallback(() => setPreviewEntryUid(null), [])
+  const handlePlay = useCallback((src, entry) => {
+    setCurrentAudio({ src, entry })
+  }, [])
+  const handleCloseAudio = useCallback(() => setCurrentAudio(null), [])
+
+  // Close stale modal when selection changes (audio persists intentionally)
+  useEffect(() => {
+    setPreviewEntryUid(null)
+  }, [selectedEntry])
+
+  // Toggle body class so fixed AudioBar doesn't obscure scrollable content
+  useEffect(() => {
+    document.body.classList.toggle('has-audio-bar', !!currentAudio)
+    return () => document.body.classList.remove('has-audio-bar')
+  }, [currentAudio])
 
   if (authState === 'loading') return <div className="auth-loading">Loading\u2026</div>;
   if (authState === 'setup')   return <SetupPage onComplete={() => setAuthState('login')} />;
   if (authState === 'login')   return <LoginPage onLogin={user => { setCurrentUser(user); setAuthState('authenticated'); }} />;
+  if (PREVIEW_ROUTE)           return <PreviewPage archiveId={PREVIEW_ROUTE.archiveId} entryUid={PREVIEW_ROUTE.entryUid} />;
 
   return (
     <AuthContext.Provider value={{ currentUser, setCurrentUser }}>
@@ -344,14 +408,34 @@ export default function App() {
           <ContextRail
             archiveId={archiveId}
             selectedEntry={selectedEntry}
+            detail={entryDetail}
             onTagFilterSet={handleTagFilterSet}
             tagNodes={tagNodes}
             onTagsRefresh={handleTagsRefresh}
             onEntryTitleChange={handleEntryTitleChange}
             onEntryDeleted={handleEntryDeleted}
             humanizeTags={humanizeTags}
+            onDetailRefresh={handleDetailRefresh}
+            onOpenPreview={handleOpenPreview}
+            onPlay={handlePlay}
           />
         </main>
+        {previewEntryUid && selectedEntry && selectedEntry.entry_uid === previewEntryUid && (
+          <PreviewModal
+            archiveId={archiveId}
+            entry={selectedEntry}
+            detail={entryDetail}
+            onClose={handleClosePreview}
+          />
+        )}
+        {currentAudio && (
+          <AudioBar
+            entry={currentAudio.entry}
+            src={currentAudio.src}
+            archiveId={archiveId}
+            onClose={handleCloseAudio}
+          />
+        )}
         <CaptureDialog
           open={captureDialogOpen}
           archiveId={archiveId}