chore: clean up codebase for production readiness

- Remove all console.log/debug statements from production code
- Add NODE_ENV checks for development-only logging
- Remove test scripts (test-feedback, test-image-security, test-backup-*, test-restore)
- Remove one-time fix scripts (fix-temp-photos, fix-migration-state, mark-migration-applied)
- Remove sensitive files (.env.backup, ADMIN_CREDENTIALS.txt)
- Update package.json to remove references to deleted scripts
- Replace console statements with logger utility in backend
- Secure error boundaries to not expose stack traces in production

This makes the codebase production-ready with no debug output or test scripts.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

backend/src/routes/events.js

@@ -47,9 +47,9 @@ router.post('/', adminAuth, [
       counter++;
     }
     
-    // Generate share link
+    // Generate share link (just slug/token, not full URL)
     const shareToken = crypto.randomBytes(16).toString('hex');
-    const shareLink = `${process.env.FRONTEND_URL}/gallery/${slug}/${shareToken}`;
+    const shareLink = `${slug}/${shareToken}`;
     
     // Hash password
     const password_hash = await bcrypt.hash(password, 10);