feat: mid-session status updates — ticket notes, client updates, email drafts

Engineers can now generate AI-powered status updates during active FlowPilot
sessions and after resolve/escalate. Three audiences (Ticket Notes, Client
Update, Email Draft) with Quick/Detailed length options. Copy to clipboard
with one click. Client names auto-inserted from intake/PSA context.

Backend: new endpoint POST /ai-sessions/{id}/status-update with audience-aware
system prompts. Frontend: StatusUpdateModal with 2-step selection flow,
Share Update button in action bar, Share Resolution/Escalation on completed
sessions. Also updates Solutions Library spec with Community tier design.

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

frontend/src/components/flowpilot/index.ts

@@ -13,3 +13,4 @@ export { SessionBriefing } from './SessionBriefing'
 export { ProposalCard } from './ProposalCard'
 export { ProposalDetail } from './ProposalDetail'
 export { InSessionScriptGenerator } from './InSessionScriptGenerator'
+export { StatusUpdateModal } from './StatusUpdateModal'