Add strict types and type hints across API

Apply strict_types and extensive type declarations throughout the API and models, improving type safety and error handling. Key changes: add declare(strict_types=1) to many files; convert properties, method parameters and return values to typed signatures (PDO, arrays, ints, strings, bools, nullables); switch exception handling to Throwable in index and Router; improve Router, controllers and model method signatures and nullability handling; refine file/image serving security checks and headers in ImageController; strengthen Database typing and initialization methods; return explicit types from BaseModel CRUD helpers and counting; update Media/Cast/Adult/Game/Console/Settings controllers and models to use typed methods, better validation, and clearer update/create return types. Also add AGENTS.md (agent skills index), update README with Swagger/OpenAPI usage instructions, and add /.windsurf to .gitignore. These changes aim to harden runtime correctness, make intended contracts explicit, and prepare the codebase for easier maintenance and static analysis.

api/models/Console.php

@@ -1,21 +1,24 @@
 <?php
 
+declare(strict_types=1);
+
 require_once __DIR__ . '/MediaType.php';
 
 class Console extends MediaType {
-    protected function getType() {
+    protected function getType(): string {
         return 'Console';
     }
-    
-    protected function getTypeSpecificFields() {
+
+    protected function getTypeSpecificFields(): array {
         return [];
     }
-    
-    protected function validateTypeSpecificFields($data) {
+
+    protected function validateTypeSpecificFields(array $data): array {
         // Console spezifische Validierung
+        return $data;
     }
-    
-    public function search($filters = [], $page = 1, $limit = 20) {
+
+    public function search(array $filters = [], int $page = 1, int $limit = 20): array {
         // Nur Consoles suchen
         $filters['type'] = 'Console';
         return parent::search($filters, $page, $limit);