feat(v2): user-level privilege model + cold DM infra + init-first-agent skill

Replaces the agent-group-centric "main group" concept with user-level
privileges and adds the cold-DM infrastructure needed for proactive
outbound messaging (pairing, approvals, welcome flows).

Privilege model
- New tables: users, user_roles (owner global-only; admin global or
  scoped to an agent_group), agent_group_members (explicit non-
  privileged access; admin/owner imply membership), user_dms (cold-DM
  resolution cache).
- Removed agent_groups.is_admin, messaging_groups.admin_user_id. Replaced
  with messaging_groups.unknown_sender_policy (strict | request_approval
  | public) for per-chat unknown-sender gating.
- src/access.ts: canAccessAgentGroup, pickApprover, pickApprovalDelivery.
- src/router.ts: access gate on every inbound, honoring
  unknown_sender_policy for unknown senders.
- src/channels/telegram.ts: pairing interceptor upserts the paired user
  and promotes them to owner if hasAnyOwner() is false (first-pair-wins).

Cold DM infrastructure
- ChannelAdapter.openDM?(handle) — optional method. Chat-SDK-bridge wires
  it to chat.openDM() for resolution-required channels (Discord, Slack,
  Teams, Webex, gChat); direct-addressable channels (Telegram, WhatsApp,
  iMessage, Matrix, Resend) fall through to the handle directly.
- src/user-dm.ts: ensureUserDm(userId) — resolves + caches via user_dms.

Approval routing
- onecli-approvals + delivery use pickApprover + pickApprovalDelivery:
  scoped admins → global admins → owners (dedup), first reachable via
  ensureUserDm, same-channel-kind tie-break. Approvals land in the
  approver's DM, not the origin chat.

Delivery fixes
- delivery.ts ACL rejection now throws instead of returning undefined —
  the outer loop previously marked rejected messages as delivered.
- Implicit-origin allow: session.messaging_group_id === target skips the
  destination check.
- createMessagingGroupAgent auto-creates the companion agent_destinations
  row (normalized local_name from the messaging group's name, collision-
  broken within the agent's namespace).

Container
- container-runner.ts: /workspace/global always read-only; drops
  NANOCLAW_IS_ADMIN; adds NANOCLAW_ADMIN_USER_IDS (owners + global admins
  + scoped admins for this agent group). Agent-runner poll-loop gates
  slash commands against that set.

New skill: /init-first-agent
- Walks the operator through standing up the first agent for a channel:
  channel pick → identity lookup (reads each channel SKILL.md's
  ## Channel Info > how-to-find-id) → DM platform_id resolution (direct-
  addressable, cold-DM via "user DMs bot first + sqlite lookup", or
  Telegram pair-code fallback) → run scripts/init-first-agent.ts →
  verify via tail of nanoclaw.log.
- scripts/init-first-agent.ts: parameterized helper that upserts the
  user + grants owner (if none), creates dm-with-<display-name> agent
  group + initGroupFilesystem, reuses/creates the DM messaging_group,
  wires it (auto-creates destination), resolves the session, and writes
  a kind:'chat' / sender:'system' welcome message into inbound.db. Host
  sweep wakes the container and the agent DMs the operator via the
  normal delivery path.

/manage-channels rewrite
- Drops --is-main / --jid / main-vs-non-main isolation references.
- First-channel flow delegates to /init-first-agent.
- Explains createMessagingGroupAgent auto-creates destinations.
- Adds a privileged-users show section.

setup/
- register.ts: drop --is-main, --jid, --local-name, --trigger
  requiresTrigger defaults; call initGroupFilesystem; normalize to
  v2 schema (no is_admin, no admin_user_id, sets unknown_sender_policy
  'strict'); let createMessagingGroupAgent handle the destination row.
- pair-telegram.ts: emit PAIRED_USER_ID (namespaced "telegram:<id>")
  instead of ADMIN_USER_ID; update header comment.
- register.test.ts deleted — was v1-only, tested a registered_groups
  table that no longer exists.

Docs
- v2-architecture-diagram.{md,html}: ER diagram updated to drop
  is_admin/admin_user_id, add unknown_sender_policy, and include
  users/user_roles/agent_group_members/user_dms.
- v2-architecture-draft.md: approval-routing paragraph rewritten for
  pickApprover/pickApprovalDelivery/ensureUserDm; SQL schema block
  updated; admin-verification paragraph references
  NANOCLAW_ADMIN_USER_IDS.
- v2-setup-wiring.md: entity-model sketch rewritten.
- v2-checklist.md: marked privilege refactor / container filtering /
  approval routing / unknown-sender gating done; removed obsolete
  admin_user_id and main-vs-non-main items.

Scripts
- scripts/init-first-agent.ts (new) replaces scripts/welcome-owner-dm.ts
  (removed; welcome-owner was a Discord-specific one-off).
- test-v2-host.ts, test-v2-channel-e2e.ts, seed-discord.ts: drop
  is_admin + admin_user_id, use unknown_sender_policy.

Tests
- src/access.test.ts (new): 14 tests for canAccessAgentGroup, role
  helpers, pickApprover, ensureUserDm, pickApprovalDelivery.
- src/db/db-v2.test.ts: adds 3 tests for the auto-created
  agent_destinations row (normalized name, no duplicates, collision
  break within an agent group).
- host-core.test.ts, channel-registry.test.ts: updated fixtures to
  use unknown_sender_policy: 'public' where the test exercises routing
  rather than the access gate.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/db/db-v2.test.ts

@@ -8,7 +8,6 @@ import {
   getAgentGroup,
   getAgentGroupByFolder,
   getAllAgentGroups,
-  getAdminAgentGroup,
   updateAgentGroup,
   deleteAgentGroup,
   createMessagingGroup,
@@ -66,7 +65,6 @@ describe('agent groups', () => {
     id: 'ag-1',
     name: 'Test Agent',
     folder: 'test-agent',
-    is_admin: 0,
     agent_provider: null,
     container_config: null,
     created_at: now(),
@@ -93,14 +91,6 @@ describe('agent groups', () => {
     expect(getAllAgentGroups()).toHaveLength(2);
   });
 
-  it('should find admin group', () => {
-    createAgentGroup(ag());
-    createAgentGroup({ ...ag(), id: 'ag-admin', name: 'Admin', folder: 'admin', is_admin: 1 });
-    const admin = getAdminAgentGroup();
-    expect(admin).toBeDefined();
-    expect(admin!.id).toBe('ag-admin');
-  });
-
   it('should update', () => {
     createAgentGroup(ag());
     updateAgentGroup('ag-1', { name: 'Updated' });
@@ -128,7 +118,7 @@ describe('messaging groups', () => {
     platform_id: 'chan-123',
     name: 'General',
     is_group: 1,
-    admin_user_id: 'user-1',
+    unknown_sender_policy: 'strict' as const,
     created_at: now(),
   });
 
@@ -172,7 +162,6 @@ describe('messaging group agents', () => {
       id: 'ag-1',
       name: 'Agent',
       folder: 'agent',
-      is_admin: 0,
       agent_provider: null,
       container_config: null,
       created_at: now(),
@@ -183,7 +172,7 @@ describe('messaging group agents', () => {
       platform_id: 'chan-1',
       name: 'Gen',
       is_group: 1,
-      admin_user_id: null,
+      unknown_sender_policy: 'strict',
       created_at: now(),
     });
   });
@@ -212,7 +201,6 @@ describe('messaging group agents', () => {
       id: 'ag-2',
       name: 'Agent2',
       folder: 'agent2',
-      is_admin: 0,
       agent_provider: null,
       container_config: null,
       created_at: now(),
@@ -243,6 +231,47 @@ describe('messaging group agents', () => {
   it('should enforce foreign key on agent_group_id', () => {
     expect(() => createMessagingGroupAgent({ ...mga(), agent_group_id: 'nonexistent' })).toThrow();
   });
+
+  it('auto-creates an agent_destinations row for the wiring', async () => {
+    const { getDestinationByTarget, getDestinations } = await import('./agent-destinations.js');
+    createMessagingGroupAgent(mga());
+
+    const dest = getDestinationByTarget('ag-1', 'channel', 'mg-1');
+    expect(dest).toBeDefined();
+    expect(dest!.local_name).toBe('gen'); // normalized from mg.name='Gen'
+    expect(getDestinations('ag-1')).toHaveLength(1);
+  });
+
+  it('does not duplicate destination row on re-wiring', async () => {
+    const { getDestinations } = await import('./agent-destinations.js');
+    createMessagingGroupAgent(mga());
+    // Re-create the same wiring throws (PK unique), but even if we got the
+    // row in some other way (e.g. via createDestination directly followed
+    // by createMessagingGroupAgent), we should not end up with two rows.
+    deleteMessagingGroupAgent('mga-1');
+    createMessagingGroupAgent(mga());
+    expect(getDestinations('ag-1')).toHaveLength(1);
+  });
+
+  it('breaks local_name collisions within an agent group', async () => {
+    const { getDestinations } = await import('./agent-destinations.js');
+    // Two messaging groups with the same `name` wired to the same agent
+    // should get distinct local_names (gen, gen-2).
+    createMessagingGroupAgent(mga());
+    createMessagingGroup({
+      id: 'mg-2',
+      channel_type: 'discord',
+      platform_id: 'chan-2',
+      name: 'Gen',
+      is_group: 1,
+      unknown_sender_policy: 'strict',
+      created_at: now(),
+    });
+    createMessagingGroupAgent({ ...mga(), id: 'mga-2', messaging_group_id: 'mg-2' });
+
+    const dests = getDestinations('ag-1').map((d) => d.local_name).sort();
+    expect(dests).toEqual(['gen', 'gen-2']);
+  });
 });
 
 // ── Sessions ──
@@ -253,7 +282,6 @@ describe('sessions', () => {
       id: 'ag-1',
       name: 'Agent',
       folder: 'agent',
-      is_admin: 0,
       agent_provider: null,
       container_config: null,
       created_at: now(),
@@ -264,7 +292,7 @@ describe('sessions', () => {
       platform_id: 'chan-1',
       name: 'Gen',
       is_group: 1,
-      admin_user_id: null,
+      unknown_sender_policy: 'strict',
       created_at: now(),
     });
   });
@@ -349,7 +377,6 @@ describe('pending questions', () => {
       id: 'ag-1',
       name: 'Agent',
       folder: 'agent',
-      is_admin: 0,
       agent_provider: null,
       container_config: null,
       created_at: now(),