Show WhatsApp channel peer next to Agent Preset in session header (4.9.1-ops.20).

Plugins inject conversation.session.header.actions; resolve sessionId back to the bound chat and render nickname/phone or group title.

Co-authored-by: Cursor <cursoragent@cursor.com>

test/channels/shared/channel-peer.test.mjs

@@ -0,0 +1,80 @@
+import assert from 'node:assert/strict';
+import { mkdtemp, rm } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { test } from 'node:test';
+
+import {
+  parseConversationKey,
+  resolveChannelPeerFromBinding,
+} from '../../../src/channels/shared/channel-peer.mjs';
+import { ConversationStateStore } from '../../../src/channels/shared/conversation-state-store.mjs';
+
+test('parseConversationKey covers direct, shared group, and per-user group', () => {
+  assert.deepEqual(parseConversationKey('direct:8618111111111@s.whatsapp.net'), {
+    kind: 'direct',
+    conversationId: '8618111111111@s.whatsapp.net',
+    senderId: null,
+  });
+  assert.deepEqual(parseConversationKey('group:120363@g.us'), {
+    kind: 'group',
+    conversationId: '120363@g.us',
+    senderId: null,
+  });
+  assert.deepEqual(parseConversationKey('group:120363@g.us:user:8618222222222@s.whatsapp.net'), {
+    kind: 'group',
+    conversationId: '120363@g.us',
+    senderId: '8618222222222@s.whatsapp.net',
+  });
+  assert.equal(parseConversationKey(''), null);
+  assert.equal(parseConversationKey('other:x'), null);
+});
+
+test('resolveChannelPeerFromBinding builds DM and group labels from access grant', () => {
+  const grant = {
+    contacts: [{ phone: '8618222222222', pushName: 'Alice' }],
+    groups: {
+      '120363@g.us': { title: 'Ops Room', admins: [], members: [] },
+    },
+  };
+  const direct = resolveChannelPeerFromBinding({
+    channel: 'whatsapp',
+    botId: 'bot-1',
+    conversationKey: 'direct:8618222222222@s.whatsapp.net',
+    grant,
+  });
+  assert.equal(direct.label, 'Alice · 8618222222222');
+  assert.equal(direct.kind, 'direct');
+  assert.equal(direct.phone, '8618222222222');
+
+  const groupUser = resolveChannelPeerFromBinding({
+    channel: 'whatsapp',
+    botId: 'bot-1',
+    conversationKey: 'group:120363@g.us:user:8618222222222@s.whatsapp.net',
+    grant,
+  });
+  assert.equal(groupUser.label, 'Ops Room · Alice');
+  assert.equal(groupUser.groupTitle, 'Ops Room');
+
+  const groupShared = resolveChannelPeerFromBinding({
+    channel: 'whatsapp',
+    botId: 'bot-1',
+    conversationKey: 'group:120363@g.us',
+    grant,
+  });
+  assert.equal(groupShared.label, '群 · Ops Room');
+});
+
+test('ConversationStateStore.keyForSession reverses session bindings', async () => {
+  const root = await mkdtemp(join(tmpdir(), 'dsh-im-channel-peer-'));
+  try {
+    const store = await new ConversationStateStore(join(root, 'state.json')).load();
+    await store.setSession('direct:u1', 'session-a');
+    await store.setSession('group:g1:user:u2', 'session-b');
+    assert.equal(store.keyForSession('session-a'), 'direct:u1');
+    assert.equal(store.keyForSession('session-b'), 'group:g1:user:u2');
+    assert.equal(store.keyForSession('missing'), null);
+  } finally {
+    await rm(root, { recursive: true, force: true });
+  }
+});