feat(contracts,server,web): files G6–G8 fields and identify S-7 contract

- G6: FileRoot.pendingCount/pendingPartial for download roots (same rule as the
  unidentified filter, recursive, cached 5 min, invalidated by files.changed)
- G7: FileEntry.parsedHint from parseReleasePath (file + parent dirs); the web
  subline uses it and no longer parses names itself
- G8: FileIdentifyCandidate.posterUrl (TMDB poster_path via adapter and
  catalog.lookup, local entities from metadata.posterPath); thumbnails in the
  identify panel
- S-7 contract: FilesIdentifyResult.remoteTaskId/remotePending,
  MediaServerInventory.partial, EventType identify.completed with
  IdentifyCompletedPayload; identify panel (useIdentifyLive) and organize wizard
  merge remote results by root + path, buffering events that beat the response

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/adapters/src/tmdb/tmdb.test.ts

@@ -34,7 +34,13 @@ describe("TmdbClient 搜索与详情", () => {
     const { tmdb } = await setup();
     const r = await tmdb.search("奥本海默", { type: "movie" });
     expect(r).toHaveLength(1);
-    expect(r[0]).toMatchObject({ provider: "tmdb", entityType: "movie", externalId: "872585", year: 2023 });
+    expect(r[0]).toMatchObject({
+      provider: "tmdb",
+      entityType: "movie",
+      externalId: "872585",
+      year: 2023,
+      posterPath: "/oppenheimer.jpg",
+    });
     expect(r[0]!.title).toBe("奥本海默");
     expect(r[0]!.titles.map((t) => `${t.kind}:${t.lang}:${t.text}`)).toEqual([
       "localized:zh-CN:奥本海默",