fix(pi): preserve restart recovery during graceful shutdown

Intentional runtime release emitted a failed turn and consumed the saved recovery intent. Keep process-exit cleanup while reserving turn failure for exits of a live session.

packages/server/src/server/agent/providers/pi/agent.test.ts

@@ -2183,6 +2183,25 @@ describe("PiRpcAgentSession", () => {
     ]);
   });
 
+  test.each([false, true])(
+    "closing Pi releases an active turn without publishing a terminal outcome (autonomous=%s)",
+    async (autonomous) => {
+      const { pi, session, events } = await createSession();
+      if (autonomous) {
+        pi.latestSession().emit({ type: "agent_start" });
+        pi.latestSession().emit({ type: "turn_start" });
+      } else {
+        await session.startTurn("keep working");
+      }
+      const before = events.turnLifecycleEvents();
+
+      await session.close();
+
+      expect(pi.latestSession().closeCalls).toBe(1);
+      expect(events.turnLifecycleEvents()).toEqual(before);
+    },
+  );
+
   test("fails the active turn when the Pi process exits mid-turn", async () => {
     const { pi, session, events } = await createSession();
 

packages/server/src/server/agent/providers/pi/agent.ts

@@ -2204,12 +2204,16 @@ export class PiRpcAgentSession implements AgentSession {
     this.pendingSettledMessages = null;
     this.pendingSteerSubmissions.length = 0;
     this.clearNoTurnBuffers();
-    this.emit({
-      type: "turn_failed",
-      provider: this.provider,
-      turnId,
-      error,
-    });
+    // Releasing the runtime is not a failed turn: restart recovery still owns
+    // unfinished work after the session has been intentionally closed.
+    if (!this.closed) {
+      this.emit({
+        type: "turn_failed",
+        provider: this.provider,
+        turnId,
+        error,
+      });
+    }
   }
 
   private handleSessionEvent(event: PiAgentSessionEvent): void {

packages/server/src/server/agent/providers/pi/test-utils/fake-pi.ts

@@ -427,6 +427,10 @@ export class FakePiSession implements PiRuntimeSession {
 
   async close(): Promise<void> {
     this.closeCalls += 1;
+    this.emit({
+      type: "process_exit",
+      error: "Pi RPC process exited with code 0 and signal null",
+    });
   }
 
   emit(event: PiRuntimeEvent): void {