chore: add Supabase keepalive endpoint and schedule cron job

app/api/cron/supabase-keepalive/route.ts

@@ -0,0 +1,42 @@
+import 'server-only'
+import { NextRequest, NextResponse } from 'next/server'
+import { createAdminClient } from '@/lib/database/supabase-admin'
+
+export async function GET(request: NextRequest) {
+  const cronSecret = process.env.CRON_SECRET
+  const authorization = request.headers.get('authorization')
+
+  if (!cronSecret || authorization !== `Bearer ${cronSecret}`) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  const supabase = createAdminClient()
+
+  if (!supabase) {
+    return NextResponse.json(
+      { error: 'Supabase service role is not configured' },
+      { status: 500 }
+    )
+  }
+
+  const startedAt = Date.now()
+  const { error, count } = await supabase
+    .from('profiles')
+    .select('id', { count: 'exact', head: true })
+    .limit(1)
+
+  if (error) {
+    console.error('Supabase keepalive failed:', error.message)
+    return NextResponse.json(
+      { error: 'Supabase keepalive failed' },
+      { status: 502 }
+    )
+  }
+
+  return NextResponse.json({
+    ok: true,
+    checked: 'profiles',
+    count,
+    latencyMs: Date.now() - startedAt,
+  })
+}

vercel.json

@@ -0,0 +1,8 @@
+{
+  "crons": [
+    {
+      "path": "/api/cron/supabase-keepalive",
+      "schedule": "0 3 * * *"
+    }
+  ]
+}