single source of truth for pi config via ~/.pi/agent

auth.json stores api keys, models.json stores local providers directly.
no more copies, sync layers, or per-user config generation.
docker containers mount pi config read-only.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/servers/api/pi/list-models.ts

@@ -24,7 +24,7 @@ const parseSize = (s?: string): number => {
   return Math.round(num);
 };
 
-export async function listPiModels(envKeys: Record<string, string>): Promise<ModelInfo[]> {
+export async function listPiModels(): Promise<ModelInfo[]> {
   if (cachedModels && Date.now() - cacheTimestamp < CACHE_TTL_MS) {
     return cachedModels;
   }
@@ -33,7 +33,7 @@ export async function listPiModels(envKeys: Record<string, string>): Promise<Mod
     const proc = Bun.spawn(['pi', '--list-models'], {
       stdout: 'pipe',
       stderr: 'pipe',
-      env: { ...process.env, ...envKeys, PI_CODING_AGENT_DIR: PI_CONFIG_DIR },
+      env: { ...process.env, PI_CODING_AGENT_DIR: PI_CONFIG_DIR },
     });
 
     const output = await new Response(proc.stdout).text();