feat: Phase 5 & 6 — usability, compliance hardening, analytics

Phase 5 (usability + compliance):
- In-app notification bell/badge: migration 016 adds read state + per-user
  RLS + create_in_app_notification SECURITY DEFINER RPC; /api/notifications;
  wired into incident creation, CAPA assign/verify, escalation cron
- Incident closure: new POST /api/incidents/[id]/close (requires verification
  status + all CAPAs verified); migration 017 locks closed incidents at DB
  level (update/delete triggers) with append-only incident_addenda + UI panel
- Server-side pagination on HSE/supervisor incident inboxes (.range, 25/page)
- Investigation form: alcohol/urine test result + witness statement refs
  (existing schema columns, now editable)
- Type-specific intake fields: migration 018 adds incidents.type_details
  JSONB; whitelist validation; environmental/asset/security/fire field
  groups in report form; EN/MS/ZH labels; offline queue support
- JKKP 8 annual register CSV export (/api/reports/jkkp8) + dashboard button
  + January statutory deadline banner
- Admin page: user invite (service-role client), role/site/active management,
  site + zone CRUD with QR report links — replaces Phase 0 stub
- Evidence gallery thumbnails via Supabase render transform with fallback

Phase 6 (analytics):
- 12-month stacked trend chart (leading/lagging/other) + top root causes
  (lib/dashboard/trends.ts pure helpers)
- AI rising-risk zones: /api/dashboard/ai/risk-flags aggregates 90-day
  zone stats, claude-opus-4-8 forced tool_use, panel on HSE + management
  dashboards, suggestion audit-logged

Also fixes 9 pre-existing missing /ims basePath prefixes in client fetches
and download links.

132 tests passing, tsc clean, next build clean.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CPf5Rc8QPx6V8KLEEgfKEQ

app/api/notifications/route.ts

@@ -0,0 +1,53 @@
+export const dynamic = 'force-dynamic'
+
+import { NextRequest, NextResponse } from 'next/server'
+import { createClient } from '@/lib/supabase/server'
+
+export async function GET() {
+  const supabase = await createClient()
+  const { data: { user }, error: authError } = await supabase.auth.getUser()
+  if (authError || !user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+
+  const { data: notifications, error } = await supabase
+    .from('notifications_log')
+    .select('id, title, link, incident_id, capa_id, sent_at, read_at')
+    .eq('channel', 'in_app')
+    .eq('recipient_user_id', user.id)
+    .order('sent_at', { ascending: false })
+    .limit(20)
+
+  if (error) return NextResponse.json({ error: 'Fetch failed' }, { status: 500 })
+
+  const { count } = await supabase
+    .from('notifications_log')
+    .select('id', { count: 'exact', head: true })
+    .eq('channel', 'in_app')
+    .eq('recipient_user_id', user.id)
+    .is('read_at', null)
+
+  return NextResponse.json({ notifications: notifications ?? [], unread: count ?? 0 })
+}
+
+export async function POST(request: NextRequest) {
+  const supabase = await createClient()
+  const { data: { user }, error: authError } = await supabase.auth.getUser()
+  if (authError || !user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+
+  const body: { ids?: string[]; all?: boolean } = await request.json().catch(() => ({}))
+
+  let query = supabase
+    .from('notifications_log')
+    .update({ read_at: new Date().toISOString() })
+    .eq('recipient_user_id', user.id)
+    .is('read_at', null)
+
+  if (!body.all) {
+    if (!Array.isArray(body.ids) || body.ids.length === 0)
+      return NextResponse.json({ error: 'ids required unless all:true' }, { status: 422 })
+    query = query.in('id', body.ids)
+  }
+
+  const { error } = await query
+  if (error) return NextResponse.json({ error: 'Update failed' }, { status: 500 })
+  return NextResponse.json({ ok: true })
+}