perf: speed up model/agent readiness on the initial draft

Load startup config under the owning project's directory key (resolving from a
worktree directory when needed) so the auto-opened draft, which activates the
project, finds a ready providers/agents snapshot instead of triggering a second
load. Also dedupe app.agents: listAgents now takes the directory directly and
shares an in-flight request, so the config store and agents store no longer
issue duplicate agent fetches at startup.

packages/ui/src/lib/opencode/client.ts

@@ -229,6 +229,7 @@ class OpencodeService {
   private currentDirectory: string | undefined = undefined;
   private directoryContextQueue: Promise<void> = Promise.resolve();
   private listDirectoryInFlight: Map<string, Promise<FilesystemEntry[]>> = new Map();
+  private listAgentsInFlight: Map<string, Promise<Agent[]>> = new Map();
   private listDirectoryCache: Map<string, { entries: FilesystemEntry[]; expiresAt: number }> = new Map();
 
   constructor(baseUrl: string = DEFAULT_BASE_URL) {
@@ -1294,14 +1295,34 @@ class OpencodeService {
    * useAgentsStore) can observe failure and retry; silently returning an
    * empty list would defeat retries and clear the cached agent list.
    */
-  async listAgents(): Promise<Agent[]> {
-    const response = await this.client.app.agents(
-      this.currentDirectory ? { directory: this.currentDirectory } : undefined
-    );
-    if (response.error) {
-      throw new Error(`app.agents failed: ${formatSdkError(response.error)}`);
+  async listAgents(directory?: string | null): Promise<Agent[]> {
+    // Pass the directory explicitly so we don't depend on (and serialize behind)
+    // withDirectory's shared context queue. Concurrent callers for the same
+    // directory (e.g. config store + agents store at startup) share one request.
+    const effectiveDirectory = this.normalizeCandidatePath(directory) ?? directory ?? this.currentDirectory ?? undefined;
+    const key = effectiveDirectory ?? '';
+
+    const existing = this.listAgentsInFlight.get(key);
+    if (existing) {
+      return existing;
+    }
+
+    const request = (async () => {
+      const response = await this.client.app.agents(
+        effectiveDirectory ? { directory: effectiveDirectory } : undefined
+      );
+      if (response.error) {
+        throw new Error(`app.agents failed: ${formatSdkError(response.error)}`);
+      }
+      return response.data || [];
+    })();
+
+    this.listAgentsInFlight.set(key, request);
+    try {
+      return await request;
+    } finally {
+      this.listAgentsInFlight.delete(key);
     }
-    return response.data || [];
   }
 
   // SSE infrastructure removed — EventPipeline in sync/event-pipeline.ts handles