Migrate all IPC call sites to typed tauri-specta commands.*

Replace the remaining ~155 untyped invoke() calls across stores, services,
components, and routes with the generated commands.* wrappers from
$lib/api/bindings, so every IPC call is compile-time-checked against the
command signatures.

- Register repository_get_subtitle_url and repository_get_video_download_url
  in specta_builder() and the invoke_handler; regenerate bindings.ts.
- Source duplicated wire types (AutoplaySettings, CacheConfig, Session,
  ConnectivityStatus, audio/video settings, etc.) from bindings.
- Fix two bugs surfaced by the typed wrappers:
  - VideoDownloadButton passed an un-awaited Promise as the stream URL.
  - setAutoplaySettings omitted the required userId argument.
- Update unit tests asserting the old invoke(name, args) shape.
- Remove the five param-naming guard tests; the compiler and codegen now
  enforce what they checked.

svelte-check: 0 errors. vitest: green. cargo test --lib: green.

src/lib/components/library/TrackList.svelte

@@ -1,5 +1,6 @@
 <script lang="ts">
-  import { invoke } from "@tauri-apps/api/core";
+  import { commands } from "$lib/api/bindings";
+  import type { PlayTracksContext } from "$lib/api/bindings";
   import { goto } from "$app/navigation";
   import { queue } from "$lib/stores/queue";
   import { auth } from "$lib/stores/auth";
@@ -62,14 +63,11 @@
       if (context && context.type === "album") {
         const repositoryHandle = repo.getHandle();
         console.log(`[TrackList] Playing track: "${track.name}" (ID: ${track.id}, index in list: ${index})`);
-        await invoke("player_play_album_track", {
-          repositoryHandle,
-          request: {
-            albumId: context.albumId,
-            albumName: context.albumName,
-            trackId: track.id,
-            shuffle: false,
-          },
+        await commands.playerPlayAlbumTrack(repositoryHandle, {
+          albumId: context.albumId,
+          albumName: context.albumName,
+          trackId: track.id,
+          shuffle: false,
         });
         return;
       }
@@ -80,7 +78,7 @@
       const trackIds = tracks.map((t) => t.id);
 
       // Determine context for queue
-      let playContext;
+      let playContext: PlayTracksContext;
       if (context?.type === "playlist") {
         playContext = {
           type: "playlist",
@@ -88,17 +86,14 @@
           playlistName: context.playlistName,
         };
       } else {
-        playContext = { type: "custom" };
+        playContext = { type: "custom", label: null };
       }
 
-      await invoke("player_play_tracks", {
-        repositoryHandle,
-        request: {
-          trackIds,
-          startIndex: index,
-          shuffle: false,
-          context: playContext,
-        },
+      await commands.playerPlayTracks(repositoryHandle, {
+        trackIds,
+        startIndex: index,
+        shuffle: false,
+        context: playContext,
       });
 
       // Queue will auto-update from Rust backend event