Implement Phase 2 improvements

Implement slug uniqueness constraints, foreign key validation, and rate limiting.

supabase/functions/process-selective-approval/index.ts

@@ -1,6 +1,7 @@
 import { serve } from 'https://deno.land/std@0.168.0/http/server.ts';
 import { createClient } from 'https://esm.sh/@supabase/supabase-js@2.57.4';
 import { corsHeaders } from './cors.ts';
+import { rateLimiters, withRateLimit } from '../_shared/rateLimiter.ts';
 
 const SUPABASE_URL = Deno.env.get('SUPABASE_URL') || 'https://api.thrillwiki.com';
 const SUPABASE_ANON_KEY = Deno.env.get('SUPABASE_ANON_KEY')!;
@@ -11,7 +12,8 @@ interface ApprovalRequest {
   idempotencyKey: string;
 }
 
-serve(async (req) => {
+// Main handler function
+const handler = async (req: Request) => {
   // Handle CORS preflight requests
   if (req.method === 'OPTIONS') {
     return new Response(null, { 
@@ -278,4 +280,7 @@ serve(async (req) => {
       }
     );
   }
-});
+};
+
+// Apply rate limiting: 10 requests per minute per IP (standard tier)
+serve(withRateLimit(handler, rateLimiters.standard, corsHeaders));