## Why
We want terminal tool review analytics, but the reducer should not stamp
review timing from its own wall clock.
This PR plumbs review timing through the real protocol and app-server
seams so downstream analytics can consume the emitter's timestamps
directly. Guardian reviews keep their enriched `started_at` /
`completed_at` analytics fields by deriving those legacy second-based
values from the same protocol-native millisecond lifecycle timestamps,
rather than sampling a separate analytics clock.
## What changed
- add `started_at_ms` to user approval request payloads
- add `started_at_ms` / `completed_at_ms` to guardian review
notifications
- preserve Guardian review `started_at` / `completed_at` enrichment from
the protocol-native timing source
- stamp typed `ServerResponse` analytics facts with app-server-observed
`completed_at_ms`
- thread the new timing fields through core, protocol, app-server, TUI,
and analytics fixtures
## Verification
- `cargo test -p codex-app-server outgoing_message --manifest-path
codex-rs/Cargo.toml`
- `cargo test -p codex-app-server-protocol guardian --manifest-path
codex-rs/Cargo.toml`
- `cargo test -p codex-tui guardian --manifest-path codex-rs/Cargo.toml`
- `cargo test -p codex-analytics analytics_client_tests --manifest-path
codex-rs/Cargo.toml`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/21434).
* #18748
* __->__ #21434
* #18747
* #17090
* #17089
* #20514
## Why
`codex-rs/app-server-protocol/src/protocol/v2.rs` had grown into a
single ~12k-line definition file for the entire app-server v2 API.
This is purely a mechanical refactor to break up the monolithic `v2.rs`
file that contains all app-server API v2 types into more modular files,
grouped by resource (e.g. account, thread, turn, etc.).
`just write-app-server-schema` shows no real changes, so we can be sure
that this is purely an internal organizational change.
## What changed
- Replaced the monolithic `protocol/v2.rs` with a `protocol/v2/` module
tree and a small `mod.rs` that only declares and reexports modules.
- Grouped v2 API definitions by conceptual owner, including `account`,
`apps`, `collaboration_mode`, `command_exec`, `config`, `device_key`,
`experimental_feature`, `feedback`, `fs`, `hook`, `item`, `mcp`,
`model`, `notification`, `permissions`, `plugin`, `process`, `realtime`,
`review`, `thread`, `thread_data`, `turn`, and `windows_sandbox`.
- Moved v2 tests into `protocol/v2/tests.rs` so `mod.rs` stays small.
- Kept shared protocol helpers in `protocol/v2/shared.rs`, including the
enum mirroring macro and common cross-resource types.
- Co-located resource-specific notifications and server-request payloads
with the modules that own those resources.
- Regenerated app-server protocol schema fixtures. The schema diffs are
non-semantic newline-only changes after the refactor.
## Verification
- `cargo check -p codex-app-server-protocol`
- `cargo test -p codex-app-server-protocol`
- `just write-app-server-schema`
Michael Bolin