feat(agentctl): runForumDmBridgeJourney v0.8.638

Add / update the Phase 658 batch 2 headless journey to validate the forum→DM bridge
composer prefill flow in CI-style agentctl runs.

Co-authored-by: Cursor <[email protected]>

headless.js

@@ -847,6 +847,34 @@ class HeadlessSession {
     return { threadId: active.id, parentId, dmThreadCount: count }
   }
 
+  /** Phase 658: forum → sealed DM bridge with composer prefill. */
+  async runForumDmBridgeJourney (peerUserId, peerDisplayName) {
+    if (!this.platform) throw new Error('headless not started')
+    const g = await this.createGuild({ name: 'Forum DM Bridge' })
+    const guildId = g?.guild?.id || g?.id
+    if (!guildId) throw new Error('expected guild after create')
+    await this.loadGuild(guildId)
+    await this.refreshView()
+    await this.createGuildChannel('Forum A', { type: 'forum' })
+    const active = this._lastView?.activeChannel
+    if (!active || active.type !== 'forum') throw new Error('expected active forum channel')
+    await this.ipc({
+      type: 'bridge-forum-to-dm',
+      authorUserId: peerUserId,
+      peerDisplayName,
+      excerpt: 'Phase 658 forum bridge excerpt',
+      messageId: null
+    })
+    const v = await this.refreshView()
+    if (v.mode !== 'dm') throw new Error(`expected dm mode, got ${v.mode}`)
+    if (!v.activeChannelId) throw new Error('no active dm channel after bridge')
+    const pre = v.dmComposerPrefill || ''
+    if (!String(pre).includes('forum bridge')) {
+      throw new Error(`expected composer prefill, got ${JSON.stringify(pre)}`)
+    }
+    return { channelId: v.activeChannelId, prefill: pre }
+  }
+
   async runDmVideoLiveJourney (peerUserId, peerDisplayName) {
     if (!this.platform) throw new Error('headless not started')
     await this.openDmWithPeer(peerUserId, peerDisplayName)