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/services/imageCache.ts

@@ -1,8 +1,8 @@
 // Image cache service - Handles lazy caching of thumbnails with LRU eviction
 // TRACES: UR-007 | DR-016
 
-import { invoke } from "@tauri-apps/api/core";
 import { convertFileSrc } from "@tauri-apps/api/core";
+import { commands } from "$lib/api/bindings";
 
 /**
  * Statistics about the thumbnail cache
@@ -38,11 +38,7 @@ export async function getCachedImageUrl(
 
   // Try to get cached version
   try {
-    const cachedPath = await invoke<string | null>("thumbnail_get_cached", {
-      itemId,
-      imageType,
-      tag,
-    });
+    const cachedPath = await commands.thumbnailGetCached(itemId, imageType, tag);
 
     if (cachedPath) {
       // Convert file path to asset URL for Tauri
@@ -62,12 +58,7 @@ export async function getCachedImageUrl(
   const serverImageUrl = `${serverUrl}/Items/${itemId}/Images/${imageType}?${params.toString()}`;
 
   // Trigger background caching (fire and forget)
-  invoke("thumbnail_save", {
-    itemId,
-    imageType,
-    tag,
-    url: serverImageUrl,
-  }).catch((e) => {
+  commands.thumbnailSave(itemId, imageType, tag, serverImageUrl).catch((e) => {
     // Silently fail - caching is best-effort
     console.debug("Background thumbnail cache failed:", e);
   });
@@ -80,7 +71,7 @@ export async function getCachedImageUrl(
  * Get thumbnail cache statistics
  */
 export async function getCacheStats(): Promise<ImageCacheStats> {
-  return invoke("thumbnail_get_stats");
+  return commands.thumbnailGetStats();
 }
 
 /**
@@ -89,14 +80,14 @@ export async function getCacheStats(): Promise<ImageCacheStats> {
  * @param limitBytes - The maximum cache size in bytes (0 = unlimited)
  */
 export async function setCacheLimit(limitBytes: number): Promise<void> {
-  return invoke("thumbnail_set_limit", { limitBytes });
+  await commands.thumbnailSetLimit(limitBytes);
 }
 
 /**
  * Clear all cached thumbnails
  */
 export async function clearCache(): Promise<void> {
-  return invoke("thumbnail_clear_cache");
+  await commands.thumbnailClearCache();
 }
 
 /**
@@ -105,7 +96,7 @@ export async function clearCache(): Promise<void> {
  * @param itemId - The Jellyfin item ID
  */
 export async function deleteItemCache(itemId: string): Promise<void> {
-  return invoke("thumbnail_delete_item", { itemId });
+  await commands.thumbnailDeleteItem(itemId);
 }
 
 /**