Add Nix caches and default flake package

Delete the temp entry at store_path/temp/<timestamp> in both
the hash-exists and success paths. Stop constructing the full filename
with extension and remove the early process::exit to de-duplicate
cleanup.

flake.nix

@@ -1,6 +1,18 @@
 {
   description = "Archivr - An open-source archive manager";
 
+  nixConfig = {
+    extra-substituters = [
+      "https://cache.thegeneralist01.com/"
+      "https://cache.garnix.io/"
+      "https://cache.nixos.org/"
+    ];
+    extra-trusted-public-keys = [
+      "cache.thegeneralist01.com:jkKcenR877r7fQuWq6cr0JKv2piqBWmYLAYsYsSJnT4="
+      "cache.garnix.io:CTFPyKSLcx5RMJKfLo5EEPUObbA78b0YQ2DTCJXqr9g="
+    ];
+  };
+
   inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
 
   outputs =
@@ -21,7 +33,7 @@
             pname = "archivr";
             version = "0.1.0";
             src = pkgs.lib.cleanSource ./.;
-            cargoHash = "sha256-y47+Fmp3BID86aPnLtrvzg40lOr9cHyg/38+onisK7w=";
+            cargoHash = "sha256-4m+4SMYA/rJ0eHEOc32zA2VdZI1pqzB5NenD0R0f2zM=";
             nativeBuildInputs = [ pkgs.pkg-config ];
           };
           archivr = pkgs.stdenv.mkDerivation {
@@ -49,6 +61,7 @@
           };
         in
         {
+          default = archivr;
           archivr = archivr;
           archivr-unwrapped = archivr_unwrapped;
         }

src/main.rs

@@ -77,7 +77,7 @@ enum Source {
 // INFO: yt-dlp supports a lot of sites; so, when archiving (for example) a website, the user
 // -> should be asked whether they want to archive the whole website or just the video(s) on it.
 fn determine_source(path: &str) -> Source {
-    // INFO: Extractors' URLs can be found here:
+    // INFO: Extractor URLs can be found here:
     // -> https://github.com/yt-dlp/yt-dlp/tree/dfc0a84c192a7357dd1768cc345d590253a14fe5/yt_dlp/extractor
     // TEST: X posts can have multiple videos.
 
@@ -272,13 +272,7 @@ fn main() -> Result<()> {
             // Dir or whatever. it's midnight and my brain ain't wording/braining.
             if hash_exists {
                 println!("File already archived.");
-                let _ = fs::remove_file(
-                    store_path
-                        .join("temp")
-                        .join(&timestamp)
-                        .join(format!("{timestamp}{file_extension}")),
-                );
-                process::exit(0);
+                let _ = fs::remove_file(store_path.join("temp").join(&timestamp));
             } else {
                 move_temp_to_raw(
                     &store_path
@@ -288,6 +282,7 @@ fn main() -> Result<()> {
                     &hash,
                     &store_path,
                 )?;
+                let _ = fs::remove_file(store_path.join("temp").join(&timestamp));
 
                 println!("File archived successfully.");
             }