feat: implement database management service layer with MySQL driver and API controllers

backend/app/Contracts/DatabaseDriverInterface.php

@@ -78,4 +78,9 @@ interface DatabaseDriverInterface
      * Perform batch update on a table.
      */
     public function batchUpdate(string $table, array $changes): bool;
+
+    /**
+     * Create a new database.
+     */
+    public function createDatabase(string $name, string $charset = 'utf8mb4', string $collation = 'utf8mb4_unicode_ci'): bool;
 }

backend/app/Http/Controllers/Api/SchemaController.php

@@ -266,4 +266,25 @@ class SchemaController extends Controller
             return Response::json(['error' => $e->getMessage()], 400);
         }
     }
+
+    public function createDatabase(Request $request)
+    {
+        $request->validate([
+            'name' => 'required|string|max:64',
+            'charset' => 'nullable|string|max:32',
+            'collation' => 'nullable|string|max:64',
+        ]);
+
+        try {
+            $this->initializeDriver($request);
+            $name = $request->get('name');
+            $charset = $request->get('charset', 'utf8mb4');
+            $collation = $request->get('collation', 'utf8mb4_unicode_ci');
+
+            $this->databaseService->createDatabase($name, $charset, $collation);
+            return Response::json(['message' => "Database '{$name}' created successfully"]);
+        } catch (\Exception $e) {
+            return Response::json(['error' => $e->getMessage()], 400);
+        }
+    }
 }

backend/app/Services/Database/MySqlDriver.php

@@ -448,4 +448,10 @@ class MySqlDriver implements DatabaseDriverInterface, SchemaDiscoveryInterface
         fclose($handle);
         return $path;
     }
+
+    public function createDatabase(string $name, string $charset = 'utf8mb4', string $collation = 'utf8mb4_unicode_ci'): bool
+    {
+        DB::connection($this->connectionName)->statement("CREATE DATABASE `{$name}` CHARACTER SET {$charset} COLLATE {$collation}");
+        return true;
+    }
 }

backend/app/Services/DatabaseService.php

@@ -164,4 +164,12 @@ class DatabaseService
     {
         return $this->getDriver()->batchUpdate($table, $changes);
     }
+
+    /**
+     * Create a new database.
+     */
+    public function createDatabase(string $name, string $charset = 'utf8mb4', string $collation = 'utf8mb4_unicode_ci'): bool
+    {
+        return $this->getDriver()->createDatabase($name, $charset, $collation);
+    }
 }