- Add archivr-core/src/capture.rs: Source enum, all capture helpers,
fail_run (replaces process::exit fail_archive_and_exit), and
perform_capture() as the public entry point
- Slim archivr-cli/src/main.rs to 103 lines: thin adapter over
archivr_core::capture::perform_capture
- Move all source-classification and tweet-entry tests from CLI to
archivr-core/src/capture.rs (they test core logic, belong in core)
- Add POST /api/archives/:archive_id/captures route in archivr-server:
validates non-empty locator (400), resolves archive (404), delegates
to perform_capture, returns {run_uid, status}
- Add capture dialog to browser UI: dialog markup in index.html,
showModal/submit/cancel/loading/error wiring in app.js, dialog
styles in styles.css
- 77 tests pass, clean build (0 warnings)
- 5 tag routes (list tree, create, assign, remove, search with tag=)
- Tags nav, tag tree view, tag filter badge
- Entry tag pills with remove, assign-tag form in context rail
