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/stores/sleepTimer.ts

@@ -11,7 +11,7 @@
  */
 
 import { writable, derived } from "svelte/store";
-import { invoke } from "@tauri-apps/api/core";
+import { commands } from "$lib/api/bindings";
 
 export type SleepTimerMode =
   | { kind: "off" }
@@ -39,25 +39,19 @@ function createSleepTimerStore() {
     // Methods that invoke the backend API
     async setTimeTimer(minutes: number): Promise<void> {
       const endTime = Date.now() + minutes * 60 * 1000;
-      await invoke("player_set_sleep_timer", {
-        mode: { kind: "time", endTime },
-      });
+      await commands.playerSetSleepTimer({ kind: "time", endTime });
     },
 
     async setEndOfTrackTimer(): Promise<void> {
-      await invoke("player_set_sleep_timer", {
-        mode: { kind: "endOfTrack" },
-      });
+      await commands.playerSetSleepTimer({ kind: "endOfTrack" });
     },
 
     async setEpisodesTimer(count: number): Promise<void> {
-      await invoke("player_set_sleep_timer", {
-        mode: { kind: "episodes", remaining: count },
-      });
+      await commands.playerSetSleepTimer({ kind: "episodes", remaining: count });
     },
 
     async cancel(): Promise<void> {
-      await invoke("player_cancel_sleep_timer");
+      await commands.playerCancelSleepTimer();
     },
   };
 }