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/database.php

@@ -1,9 +1,12 @@
 <?php
+
+declare(strict_types=1);
+
 require_once __DIR__ . '/config.php';
 
 class Database {
-    private $pdo;
-    
+    private ?PDO $pdo;
+
     public function __construct() {
         try {
             $dsn = 'mysql:host=' . DB_HOST . ';dbname=' . DB_NAME . ';charset=utf8mb4';
@@ -17,8 +20,8 @@ class Database {
             exit;
         }
     }
-    
-    private function initializeTables() {
+
+    private function initializeTables(): void {
         // Media-Tabelle
         $this->pdo->exec("
             CREATE TABLE IF NOT EXISTS media (
@@ -366,8 +369,8 @@ class Database {
         // Bestehende Einträge mit cleanname aktualisieren
         $this->updateExistingCleanNames();
     }
-    
-    private function updateExistingCleanNames() {
+
+    private function updateExistingCleanNames(): void {
         // Media cleanname aktualisieren
         $this->pdo->exec("
             UPDATE media 
@@ -382,8 +385,8 @@ class Database {
             WHERE cleanname IS NULL OR cleanname = ''
         ");
     }
-    
-    public function getConnection() {
+
+    public function getConnection(): PDO {
         return $this->pdo;
     }
 }