## Why
Reloading an evicted sub-agent disabled its rollout tracing, leaving later turns out of the trace. Replacement Code Mode sessions could also reuse cell IDs from earlier sessions.
## What changed
- Reattach reloaded children to the root rollout trace and emit `ThreadResumed` without duplicating `ThreadStarted`.
- Reopen existing threads during replay, preserving their identity and history while clearing stale runtime cell and terminal process mappings.
- Allocate Code Mode cell generations across sessions for both gRPC and stdio hosts to prevent ID reuse after reload.
- Record an aborted trace when session startup fails before the session loop begins.
## Testing
Add regression coverage for child eviction and reload, including a failed reload, continued inference tracing, distinct cell IDs, and preserved mail and follow-up context. Extend replay tests for history preservation and reused runtime handles, and host tests for cell IDs across session replacement and reconnection.
GitOrigin-RevId: 6c146c04b5cda9295afb7d973c0d5474b363a822
## What changed
Add an optional `preempt` signal to `CodeModeSession::execute` and `CodeModeSession::wait` so callers can end an observation early while the cell continues running and remains available for later waits.
Support the signal in the in-process runtime and across both remote transports: `operation/yield` with the negotiated `yield-observation` capability for stdio, and `YieldObservation` for gRPC. Preserve signals received before gRPC observation registration, and retain normal timeout behavior for older hosts that lack support.
## Testing
Add runtime and transport tests covering early execute and wait yields followed by successful cell completion, yields before observation registration, and suppression of yield frames for older stdio hosts.
GitOrigin-RevId: 3f8049d8f0582be6b8f0832cc03f2d974a0b8f18
## What changed
- Load `application.network` requirements at startup and explicit config/account reloads, applying local policy before authentication and cloud configuration bootstrap.
- Block traffic when policy loading fails, cancel requests that a new policy no longer permits, and reject configuration loads based on superseded policy snapshots. Local requirements edits take effect on the next explicit reload or restart.
- Bind authenticated clients to the current account and revoke them when account ownership changes. Carry policy enforcement through backend requests, realtime connections, workload identity exchanges, and code-mode gRPC streams while preserving gRPC trailers.
- Treat denied credential refreshes as policy errors without retrying them or invalidating stored credentials.
## Testing
Add regression coverage for startup restrictions, reload ordering, cancellation after restrictive or malformed requirements edits, account revocation, gRPC destination denial, workload identity cancellation, and credential preservation after denied OAuth refresh.
GitOrigin-RevId: 0cb4c720a906397e9df06675f01ecf60d741101f