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/web/app/components/files/dir-tree.tsx

@@ -123,7 +123,7 @@ function RootNode({
           if (!open.has(k)) toggle(k);
         }}
         onDrop={onDropTo && root.writable && !offline ? (e) => onDropTo({ root: root.id, path: "" }, e) : undefined}
-        title={disabled ? (offline ? "目录离线" : "只读目录,不能作为目标") : root.hostPath}
+        title={disabled ? (offline ? "目录离线" : "只读目录，不能作为目标") : root.hostPath}
       >
         <Icon className="h-4 w-4 shrink-0 text-muted-foreground" />
         <span className="min-w-0 flex-1">
@@ -146,6 +146,12 @@ function RootNode({
                 正常
               </span>
             )}
+            {root.pendingCount ? (
+              <span className="shrink-0 text-warning">
+                待识别 {root.pendingCount}
+                {root.pendingPartial ? "+" : ""}
+              </span>
+            ) : null}
             {root.usage ? <span className="truncate">剩余 {formatBytes(root.usage.freeBytes, 1)}</span> : null}
             {!root.writable && root.kind === "library" ? <span>只读</span> : null}
           </span>
@@ -258,7 +264,7 @@ function Children({
       })}
       {q.data?.truncated ? (
         <p className="py-1 text-meta text-muted-foreground" style={{ paddingLeft: depth * 14 + 28 }}>
-          子目录过多,只列出一部分
+          子目录过多，只列出一部分
         </p>
       ) : null}
     </div>