Exclude Guardian reviewer sub-sessions from Agent Status

[twidtwid]

Summary

With Codex Approve for me enabled, Agent Status keys were filling with internal Guardian / Guardian2 reviewer sub-sessions. Pressing one failed with cannot resume a live Guardian reviewer.

Credit: Paweł Lipkowski reported the bug and diagnosed that CodexStore.recentThreads() selected recent state_5.sqlite rows without excluding internal sub-sessions, so they consumed the 12-row limit.

This change excludes those sub-sessions in SQL, before LIMIT 12, using structured metadata only (never titles). A genuine user chat titled "Guardian" stays visible. The same predicate is applied to focusedThread() and to the native helper’s thread-ID/cwd lookups so New Chat targeting cannot treat a Guardian reviewer as a valid task.

Metadata signals (each used only when the column/table exists):

Signal	How it is used
threads.thread_source	exclude 'subagent'
threads.source	if JSON, exclude when json_extract(source, '$.subagent') is present (covers Guardian and Guardian2)
threads.agent_path	exclude nested paths; /root and unset remain user-facing
thread_spawn_edges	a row whose child_thread_id is this thread is a sub-session (NOT EXISTS, so duplicate child edges cannot multiply rows before the limit)
threads.archived	exclude archived rows when the column exists

The previous LEFT JOIN thread_spawn_edges e ON e.child_thread_id = t.id could attach child status and duplicate rows before LIMIT 12. Listing now uses SELECT DISTINCT plus NOT EXISTS on spawn children, and aggregates spawn status with MAX(status) in a subquery.

Schema detection is via PRAGMA table_info / sqlite_master in TypeScript and the same probes in Swift, so older Codex databases missing these columns still work.

This PR is based on main only. It does not include Claude provider / draft PR #33 work, and it does not create a release or tag.

Validation

• Linux check-gate subset (see below)
• Full npm run check on macOS CI (includes native helper + visual QA)
• Relevant connected-device checks, or an explanation of why they do not apply — no device needed; this is a SQLite read-model filter
• No private data, credentials, proprietary Codex assets, or copied third-party source

CI check is npm run public:check && generated:check && format:check && typecheck && npm test && qa:design && build:bundle && validate.

Ran on Linux, skipping macOS-only native steps:

Step	Result
public:check	pass
generated:check	pass (no generated artifacts needed regenerating)
format:check	pass
typecheck	pass
Store / unit tests including new sqlite fixtures	pass (test/subsession-filter.test.ts, test/local-store.integration.test.ts, and the rest of the unit project except native-helper fixtures)
build:bundle	pass
streamdeck validate	pass
npm run native:build / compiled-native fixtures / qa:design	skipped — no swiftc/Xcode; no rsvg-convert/ImageMagick

Fixtures cover: Guardian excluded via each metadata signal; a user thread titled "Guardian" still shown; 12-row limit filled by real threads despite newer sub-sessions; older schema without the extra columns; focusedThread() skipping sub-sessions; a Guardian child plus its parent (including duplicate spawn edges); native archived-ID exclusion.

User impact

Agent Status keys show recent user chats instead of Approve-for-me Guardian reviewer sessions. Pressing a slot resumes that user chat. New Chat still proves a fresh user-facing thread, not a reviewer sub-session. No migration or settings change.