Stabilize paired-room orchestration and Codex app-server flow

src/session-recovery.ts

@@ -0,0 +1,26 @@
+import type { AgentOutput } from './agent-runner.js';
+
+const SESSION_RESET_PATTERNS = [
+  /An image in the conversation exceeds the dimension limit for many-image requests \(2000px\)\./i,
+  /Start a new session with fewer images\./i,
+];
+
+function toText(value: string | object | null | undefined): string[] {
+  if (!value) return [];
+  if (typeof value === 'string') return [value];
+
+  try {
+    return [JSON.stringify(value)];
+  } catch {
+    return [];
+  }
+}
+
+export function shouldResetSessionOnAgentFailure(
+  output: Pick<AgentOutput, 'result' | 'error'>,
+): boolean {
+  const texts = [...toText(output.result), ...toText(output.error)];
+  return texts.some((text) =>
+    SESSION_RESET_PATTERNS.some((pattern) => pattern.test(text)),
+  );
+}