When an unknown sender writes into a wired messaging group, surface the
situation to an admin instead of silently dropping. Flow:
1. Router → access gate → handleUnknownSender (policy='request_approval')
2. Fire-and-forget requestSenderApproval: pickApprover + pickApprovalDelivery
pick a reachable admin DM; deliver an Approve / Deny card; insert a
pending_sender_approvals row carrying the original InboundEvent JSON.
3. In-flight dedup: UNIQUE(messaging_group_id, sender_identity) — a retry
from the same stranger while pending is silently dropped, not re-carded.
4. Admin clicks → Chat SDK bridge → onAction → host response-registry.
The new handleSenderApprovalResponse in the permissions module claims
responses whose questionId matches a pending_sender_approvals row.
5. approve: addMember(stranger, agent_group) + replay the stored event via
routeInbound — the second attempt clears the gate because the user is
now known.
6. deny: delete the pending row. No denial persistence (ACTION-ITEMS item 5
decision) — a future attempt triggers a fresh card.
Schema:
- Migration 011 adds pending_sender_approvals (id, mg_id, agent_group_id,
sender_identity, sender_name, original_message JSON, approver_user_id,
created_at, UNIQUE(mg_id, sender_identity)).
- Also flips messaging_groups.unknown_sender_policy default from 'strict'
to 'request_approval' (rebuild-table). Existing rows unchanged — only
the default applied to new rows flips.
- Router auto-create for unknown platform/chat drops the hardcoded
'strict' override; schema default applies.
- src/db/schema.ts reference updated to match.
Why default-flip: users wire their DM during setup and don't discover that
'strict' means "silent drop of everyone not in user_roles/members". The
approval flow is the safe default — the admin sees the stranger, explicitly
decides. 'public' stays opt-in for truly open channels.
Failure modes (row NOT created so a future attempt can try again):
- No eligible approver configured (fresh install before first owner).
- No reachable DM for any approver.
- Delivery adapter missing.
Tests (src/modules/permissions/sender-approval.test.ts, 4 cases):
- First unknown message → card delivered + row created
- Retry while pending → dedup'd (1 card, 1 row)
- Approve → member added + message replayed + container woken
- Deny → row cleared + no member added
Closes: ACTION-ITEMS item 5.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>