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>

backend/app/services/psa/connectwise/provider.py

@@ -15,6 +15,7 @@ from app.services.psa.types import (
     PSACompany,
     PSAMember,
     PSAConfiguration,
+    PSATimeEntry,
 )
 from .client import ConnectWiseClient
 
@@ -514,6 +515,37 @@ class ConnectWiseProvider(PSAProvider):
         psa_cache.set(cache_key, ctx, ttl_seconds=300)
         return ctx
 
+    async def create_time_entry(
+        self,
+        ticket_id: str,
+        member_id: str,
+        hours: float,
+        notes: str | None = None,
+        work_type: str | None = None,
+    ) -> PSATimeEntry:
+        """Create a time entry on a CW ticket via POST /time/entries."""
+        payload: dict = {
+            "chargeToId": int(ticket_id),
+            "chargeToType": "ServiceTicket",
+            "member": {"id": int(member_id)},
+            "timeStart": datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ"),
+            "actualHours": hours,
+        }
+        if notes:
+            payload["notes"] = notes[:2000]  # CW limit
+        if work_type:
+            payload["workType"] = {"name": work_type}
+
+        data = await self._client.post("/time/entries", payload)
+        return PSATimeEntry(
+            id=str(data["id"]),
+            ticket_id=ticket_id,
+            member_id=member_id,
+            hours=data.get("actualHours", hours),
+            notes=data.get("notes"),
+            created_at=data.get("timeStart"),
+        )
+
     # ── Private helpers ───────────────────────────────────────────────
 
     @staticmethod