docs: document the inbox and agent conversations

[leynier]

Summary

• docs/orchestration.md gains an Inbox section. It covers addresses, delivery at turn end, explicit answers, statuses, expiry, the pending limit and history, the guards, waits and events, the push privacy rules, the phone allowlist, hub forwarding, agent conversations and ask --no-wait.
• docs/architecture.md gains a sentence describing the mobile inbox surface.
• The alera-cli skill gets a new inbox reference, and the alera-orchestration messaging reference explains how agents answer external questions and how to ask without waiting.

Stacked on the mobile conversations PR.

Validation

• Every command in the docs was run against an isolated runtime built from this stack: ask, wait (answered, timeout with exit 2), threads, list, show, cancel, the send --from ext: refusal, ask --no-wait, conversations and conversation.

Risk

Docs only.

[pullfrog]

Important

The paste banner tells agents to answer with a command that fails or hangs outside bash, and the status filter can hide matching threads.

Reviewed changes

Reviewed the inbox feature stacked under the docs commit: store, host verbs, CLI, desktop and mobile surfaces, and the new docs.

• Inbox store: Questions are ext: orchestration messages with expiry, a pending cap, cancellation, and a trigger-maintained revision.
• Host verbs: Local, phone, and satellite clients get an allowlisted inbox.* surface. inbox.wait stays off the phone allowlist.
• Delivery: External questions paste at turn end, coordinators read them through check, and replies are explicit orchestration.reply rows.
• Apps: Desktop and mobile share ext:user, show threads and read-only agent conversations, and route inbox reply pushes by id.
• Docs and skills: docs/orchestration.md and the CLI and orchestration skills describe the same commands.

ℹ️ Nitpicks

• The prune comment in conversation_store.rs says a thread is kept while a message is still waiting to be read. The predicate keeps state = 'queued', which is what the docs describe.

  ^{｜ Fix all ➔ ｜ Fix 👍s ➔ ｜ View workflow run ｜ Using grok-4.7 ｜ 𝕏}

[pullfrog]

ℹ️ No new issues in this delta. The open paste-banner thread is unchanged, so this is not an approval.

Reviewed changes

Reviewed the two commits since the prior review: the rewritten inbox docs and the notification-coordinator fixup.

• Thread-required send: Documented that an agent may message an inbox only by continuing the question that inbox started, or the host refuses with inbox_thread_required.
• Notification coordinator: Dropped keepAlive so the coordinator can listen to the auto-disposed unread count while the shell watches it.

  ^{｜ Fix it ➔ ｜ View workflow run ｜ Using grok-4.7 ｜ 𝕏}

[pullfrog]

✅ No new issues found.

Reviewed changes

Reviewed the rewritten docs commit since the prior review. The branch is now docs-only on the conversations feature branch, and the reply instructions match the portable banner.

• Portable reply command: Documented --body and --body-file as the banner answer, and told agents not to use a bare --body-stdin from the terminal.
• Worker ask: Noted that --no-wait keeps the worker's turn free and pastes the answer on the next turn.

  ^{｜ View workflow run ｜ Using grok-4.7 ｜ 𝕏}