feat(agent): make coordination routes opt-in and address review

Gate inspect, stage and submit behind the synced agentCoordinationEnabled
setting (default OFF, App Settings > Cross-session features, zh-CN
strings). While off, all three routes answer 403 FORBIDDEN naming the
setting, checked before session lookup; the CLI verbs print it verbatim.

Remember the attributed Codex rollout per session and re-verify only its
head on later calls, rescanning only date directories not older than it
for a /new conflict. The first walk reads 1 KiB prefixes first, so a
store of 2,100+ unrelated rollouts still attributes.

Answer unexpected inspection errors with 422 OPERATION_FAILED and log
the session id and error code only.

Read the guarded composer glyph and footer from the CLI registry: codex
workDetect.promptGlyph and a new workDetect.composerFooterLine
capability, compiled through compileVersionRegex. Codex footer effort
words are one shared list with modelDetect.screenLine.

Fix the wiki API reference link, frame the versioning policy entry as a
case of the experimental rule, join the CLAUDE.md Agent CLI paragraph,
and update the changeset, skill reference and architecture notes.

README.md

@@ -977,7 +977,7 @@ codeman tui 3                            #      attach to session 3 of that list
 
 ### `codeman agent` — session-to-session verbs in every CLI mode
 
-The skill above drives the API with `curl` and `jq` from a preamble Codeman seeds per session. Where it does not reach (a `pi` or `shell` session, a machine without `jq`), the same environment is still there (`CODEMAN_MUX=1`, `CODEMAN_SESSION_ID`, `CODEMAN_API_URL` are exported into every pane), so `codeman agent` packages the same verbs as commands. It is a thin client over the endpoints listed under [API](#api): auth and ownership apply to every endpoint, including bounded inspection and guarded input. The new `inspect`, `stage` and `submit` commands and their HTTP routes are **experimental**: commands, flags, paths, payloads and behavior may change or be removed in minor or patch releases. Pin a compatible version when automating them; see the [stability exception](docs/versioning-policy.md#experimental-agent-coordination). One line in a case's `AGENTS.md` is enough: *"other sessions: `codeman agent --help`"*.
+The skill above drives the API with `curl` and `jq` from a preamble Codeman seeds per session. Where it does not reach (a `pi` or `shell` session, a machine without `jq`), the same environment is still there (`CODEMAN_MUX=1`, `CODEMAN_SESSION_ID`, `CODEMAN_API_URL` are exported into every pane), so `codeman agent` packages the same verbs as commands. It is a thin client over the endpoints listed under [API](#api): auth and ownership apply to every endpoint, including bounded inspection and guarded input. The `inspect`, `stage` and `submit` commands and their HTTP routes are **experimental** and **opt-in**: turn on **Experimental agent coordination** in App Settings (`agentCoordinationEnabled`, synced, off by default; until then the routes answer `403 FORBIDDEN` naming it). Their commands, flags, paths, payloads and behavior may change or be removed in minor or patch releases, so pin a compatible version when automating them; see [Experimental agent coordination](docs/versioning-policy.md#experimental-agent-coordination). One line in a case's `AGENTS.md` is enough: *"other sessions: `codeman agent --help`"*.
 
 ```bash
 codeman agent ls                                          # sessions; * marks this one