Add test notification feature for push notification debugging

- Add POST /api/notifications/test endpoint to send test notifications
- Add "Send Test Notification" button to notifications settings page
- Shows success/failure feedback and removes expired subscriptions

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/notifications/test/route.ts

@@ -0,0 +1,93 @@
+import { NextResponse } from 'next/server'
+import { prisma } from '@/lib/db/prisma'
+import { withAuth, type AuthenticatedRequest } from '@/lib/auth'
+import { checkWorkspaceAccess } from '@/lib/db/workspace-access'
+import { sendPushNotification } from '@/lib/notifications/push'
+
+// POST /api/notifications/test - Send a test notification
+export const POST = withAuth(async (req: AuthenticatedRequest) => {
+  try {
+    const body = await req.json()
+    const { workspaceId } = body
+
+    if (!workspaceId) {
+      return NextResponse.json({ error: 'workspaceId required' }, { status: 400 })
+    }
+
+    // Check access
+    const access = await checkWorkspaceAccess(workspaceId, req.session.user.id)
+    if (!access) {
+      return NextResponse.json({ error: 'Access denied' }, { status: 403 })
+    }
+
+    // Get push subscriptions for this user in this workspace
+    const subscriptions = await prisma.pushSubscription.findMany({
+      where: {
+        userId: req.session.user.id,
+        workspaceId,
+      },
+    })
+
+    if (subscriptions.length === 0) {
+      return NextResponse.json(
+        { error: 'No push subscriptions found. Please enable notifications first.' },
+        { status: 404 }
+      )
+    }
+
+    let sent = 0
+    let failed = 0
+    const errors: string[] = []
+
+    for (const sub of subscriptions) {
+      try {
+        const success = await sendPushNotification(
+          {
+            endpoint: sub.endpoint,
+            p256dh: sub.p256dh,
+            auth: sub.auth,
+          },
+          {
+            title: 'Test Notification',
+            body: 'If you see this, notifications are working!',
+            tag: 'test-notification',
+            data: {
+              url: '/settings/notifications',
+              action: 'test',
+            },
+          }
+        )
+
+        if (success) {
+          sent++
+        } else {
+          // Subscription expired, remove it
+          await prisma.pushSubscription.delete({ where: { id: sub.id } })
+          failed++
+          errors.push('Subscription expired and was removed')
+        }
+      } catch (error: any) {
+        console.error('Test notification error:', error)
+        failed++
+        errors.push(error.message || 'Unknown error')
+      }
+    }
+
+    return NextResponse.json({
+      success: sent > 0,
+      sent,
+      failed,
+      total: subscriptions.length,
+      errors: errors.length > 0 ? errors : undefined,
+      message: sent > 0
+        ? `Test notification sent! Check your device.`
+        : `Failed to send notification: ${errors.join(', ')}`,
+    })
+  } catch (error) {
+    console.error('Test notification error:', error)
+    return NextResponse.json(
+      { error: 'Failed to send test notification' },
+      { status: 500 }
+    )
+  }
+})