fix: disable APP_DEBUG in production, fix .htaccess structure, add .gitignore cleanup

- Set APP_DEBUG=false in .env to prevent stack trace leakage
- Use strict comparison (===) for MD5 password migration check
- Fix duplicate rewrite rules and orphaned closing tag in .htaccess
- Remove leftover test files (cookies.txt, ci_test.txt, test-registration.php)
- Remove duplicate package-lock.json (using yarn only)
- Update .gitignore for above files

.gitignore

@@ -31,5 +31,12 @@ check-updates.sh
 /storage/debugbar/rr
 .rr.yaml
 
+# Lockfiles (kies 1 package manager)
+package-lock.json
+
+# Overgebleven test/temp bestanden
+ci_test.txt
+cookies.txt
+
 # GitHub workflows (pushen naar GitLab)
 !/.github/workflows/