fix(run): add event watchdog and secondary timeout for hasReceivedMeaningfulWork

Implements fixes from issue #1880 and #1934 to prevent exit code 130 timeout in CI environments:

- Add lastEventTimestamp to EventState for tracking when events were last received
- Add event watchdog: if no events for 30s, verify session status via direct API call
- Add secondary timeout: after 60s without meaningful work events, check for active children/todos and assume work is in progress

This prevents the poll loop from waiting for full 600s timeout when:
1. Event stream drops silently (common in CI with network instability)
2. Main session delegates to children without producing meaningful work on main session

src/cli/run/event-stream-processor.ts

@@ -35,6 +35,9 @@ export async function processEvents(
         logEventVerbose(ctx, payload)
       }
 
+      // Update last event timestamp for watchdog detection
+      state.lastEventTimestamp = Date.now()
+
       handleSessionError(ctx, payload, state)
       handleSessionIdle(ctx, payload, state)
       handleSessionStatus(ctx, payload, state)