feat(ai-session): add Phase 2 PSA integration, escalation handoff, and session management

Phase 2 of the FlowPilot-First Pivot connecting AI sessions to ConnectWise PSA:

Slice 1 — PSA Ticket Intake:
- FlowPilotEngine accepts psa_ticket intake with graceful CW API fallback
- Ticket picker on intake screen (refactored TicketPickerModal for dual-mode)
- Ticket context card in session sidebar

Slice 2 — Auto Documentation Push:
- PSA documentation service with resolution/escalation note formatting
- Time entry creation via new ConnectWise provider method
- Automatic retry scheduler (APScheduler, 5min interval, 3 retries)
- PSA push status indicators in frontend with manual retry button
- Member mapping warning when CW member not mapped

Slice 3 — Session Pause/Resume & Escalation Handoff:
- Pause/resume endpoints for same-engineer session bookmarking
- Escalation flow: requesting_escalation status, self-escalation blocked
- Enhanced escalation package with LLM-generated hypotheses/suggestions
- Pickup endpoint with continue/fresh resume modes and briefing step
- Escalation queue (sidebar nav + dedicated page)
- SessionBriefing component with continue/fresh choice UI
- EscalateModal with PSA-aware button text

Slice 4 — Mid-Session Ticket Linking:
- Link ticket retroactively with context injection into system prompt
- Link Ticket button in session sidebar

Slice 5 — FlowPilot PSA Settings:
- Settings tab on IntegrationsPage with 7 configurable options
- Stored as flowpilot_settings JSONB on PsaConnection

Database: 2 migrations (flowpilot_settings, psa_post_log changes, status constraint)

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

frontend/src/components/session/TicketPickerModal.tsx

@@ -12,11 +12,14 @@ type Mode = 'search' | 'manual'
 interface Props {
   open: boolean
   onClose: () => void
-  sessionId: string
-  onLinked: (ticketId: string, ticket: PSATicketInfo) => void
+  /** Legacy session linking mode — pass sessionId + onLinked */
+  sessionId?: string
+  onLinked?: (ticketId: string, ticket: PSATicketInfo) => void
+  /** Selection-only mode — pass onSelect instead. Returns selected ticket without linking. */
+  onSelect?: (ticketId: string, ticket: PSATicketInfo) => void
 }
 
-export function TicketPickerModal({ open, onClose, sessionId, onLinked }: Props) {
+export function TicketPickerModal({ open, onClose, sessionId, onLinked, onSelect }: Props) {
   const [mode, setMode] = useState<Mode>('search')
 
   // Search mode state
@@ -138,11 +141,22 @@ export function TicketPickerModal({ open, onClose, sessionId, onLinked }: Props)
   const handleLink = async () => {
     if (!selectedTicket || !selectedTicketId) return
 
+    // Selection-only mode — return ticket data without linking
+    if (onSelect) {
+      onSelect(selectedTicketId, selectedTicket)
+      handleReset()
+      onClose()
+      return
+    }
+
+    // Legacy session linking mode
+    if (!sessionId) return
+
     setIsLinking(true)
     setError(null)
     try {
       await sessionPsaApi.linkTicket(sessionId, selectedTicketId)
-      onLinked(selectedTicketId, selectedTicket)
+      onLinked?.(selectedTicketId, selectedTicket)
       handleReset()
     } catch (err: unknown) {
       const message =
@@ -195,7 +209,7 @@ export function TicketPickerModal({ open, onClose, sessionId, onLinked }: Props)
   }
 
   return (
-    <Modal isOpen={open} onClose={handleClose} title="Link ConnectWise Ticket" size="sm">
+    <Modal isOpen={open} onClose={handleClose} title={onSelect ? 'Select ConnectWise Ticket' : 'Link ConnectWise Ticket'} size="sm">
       <div className="space-y-4">
         {/* Mode tabs */}
         <div className="flex gap-1 rounded-lg bg-white/[0.03] p-1">
@@ -411,7 +425,7 @@ export function TicketPickerModal({ open, onClose, sessionId, onLinked }: Props)
                 loading={isLinking}
               >
                 <Ticket className="h-4 w-4" />
-                Link This Ticket
+                {onSelect ? 'Select This Ticket' : 'Link This Ticket'}
               </Button>
             </div>
           </div>