feat: implement database schema discovery and data browser interface

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

@@ -84,4 +84,24 @@ class SchemaController extends Controller
             return Response::json(['error' => $e->getMessage()], 400);
         }
     }
+    public function execute(Request $request)
+    {
+        try {
+            $this->initializeDriver($request);
+            $sql = $request->get('query');
+            
+            if (empty($sql)) {
+                return Response::json(['error' => 'Query is empty'], 400);
+            }
+
+            $results = $this->databaseService->executeQuery($sql);
+            
+            return Response::json([
+                'data' => $results,
+                'count' => count($results)
+            ]);
+        } catch (\Exception $e) {
+            return Response::json(['error' => $e->getMessage()], 400);
+        }
+    }
 }

backend/app/Services/DatabaseService.php

@@ -90,4 +90,12 @@ class DatabaseService
     {
         return $this->getDriver()->getTableCount($table);
     }
+
+    /**
+     * Execute a raw SQL query.
+     */
+    public function executeQuery(string $sql, array $bindings = []): array
+    {
+        return $this->getDriver()->query($sql, $bindings);
+    }
 }