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]>

apps/server/src/modules/sources-identity/capabilities.ts

@@ -54,6 +54,7 @@ export function registerSourcesCapabilities(registry: CapabilityRegistry, rt: ()
       externalId: string;
       title: string;
       year: number | null;
+      posterPath?: string | null;
     }[] = [];
     const tmdb = await rt().tmdb();
     if (input.includeRemote && input.query && tmdb) {
@@ -66,6 +67,7 @@ export function registerSourcesCapabilities(registry: CapabilityRegistry, rt: ()
           externalId: m.externalId,
           title: m.title,
           year: m.year,
+          posterPath: m.posterPath,
         });
       }
     }