Improve error handling and environment configuration across the application

Enhance input validation, update environment variable usage for Supabase and Turnstile, and refine image upload and auth logic for better robustness and developer experience.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: cb061c75-702e-4b89-a8d1-77a96cdcdfbb
Replit-Commit-Checkpoint-Type: intermediate_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/7cdf4e95-3f41-4180-b8e3-8ef56d032c0e/cb061c75-702e-4b89-a8d1-77a96cdcdfbb/ANdRXVZ

supabase/functions/create-novu-subscriber/index.ts

@@ -24,6 +24,48 @@ serve(async (req) => {
 
     const { subscriberId, email, firstName, lastName, phone, avatar, data } = await req.json();
 
+    // Validate required fields
+    if (!subscriberId || typeof subscriberId !== 'string' || subscriberId.trim() === '') {
+      return new Response(
+        JSON.stringify({
+          success: false,
+          error: 'subscriberId is required and must be a non-empty string',
+        }),
+        {
+          headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+          status: 400,
+        }
+      );
+    }
+
+    if (!email || typeof email !== 'string' || email.trim() === '') {
+      return new Response(
+        JSON.stringify({
+          success: false,
+          error: 'email is required and must be a non-empty string',
+        }),
+        {
+          headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+          status: 400,
+        }
+      );
+    }
+
+    // Validate email format using regex
+    const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
+    if (!emailRegex.test(email)) {
+      return new Response(
+        JSON.stringify({
+          success: false,
+          error: 'Invalid email format. Please provide a valid email address',
+        }),
+        {
+          headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+          status: 400,
+        }
+      );
+    }
+
     console.log('Creating Novu subscriber:', { subscriberId, email, firstName });
 
     const subscriber = await novu.subscribers.identify(subscriberId, {