feat: initialize backend database service architecture and implement frontend schema explorer components

backend/app/Contracts/DatabaseDriverInterface.php

@@ -24,6 +24,11 @@ interface DatabaseDriverInterface
      */
     public function getTableData(string $table, int $limit = 100, int $offset = 0): array;
 
+    /**
+     * Get the count of rows in a table.
+     */
+    public function getTableCount(string $table): int;
+
     /**
      * Get the underlying connection instance.
      */

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

@@ -65,9 +65,21 @@ class SchemaController extends Controller
     {
         try {
             $this->initializeDriver($request);
-            $limit = $request->get('limit', 100);
-            $offset = $request->get('offset', 0);
-            return Response::json($this->databaseService->getTableData($table, $limit, $offset));
+            
+            $skip = $request->get('skip', 0);
+            $take = $request->get('take', 100);
+            
+            $data = $this->databaseService->getTableData($table, $take, $skip);
+            
+            $response = [
+                'data' => $data,
+            ];
+
+            if ($request->get('requireTotalCount') === 'true') {
+                $response['totalCount'] = $this->databaseService->getTableCount($table);
+            }
+
+            return Response::json($response);
         } catch (\Exception $e) {
             return Response::json(['error' => $e->getMessage()], 400);
         }

backend/app/Services/Database/MySqlDriver.php

@@ -69,6 +69,12 @@ class MySqlDriver implements DatabaseDriverInterface, SchemaDiscoveryInterface
         return $this->query("SELECT * FROM `{$table}` LIMIT ? OFFSET ?", [$limit, $offset]);
     }
 
+    public function getTableCount(string $table): int
+    {
+        $result = $this->query("SELECT COUNT(*) as count FROM `{$table}`");
+        return (int) ($result[0]->count ?? 0);
+    }
+
     public function getForeignKeys(string $table): array
     {
         $sql = "

backend/app/Services/DatabaseService.php

@@ -82,4 +82,12 @@ class DatabaseService
     {
         return $this->getDriver()->getTableData($table, $limit, $offset);
     }
+
+    /**
+     * Get table row count.
+     */
+    public function getTableCount(string $table): int
+    {
+        return $this->getDriver()->getTableCount($table);
+    }
 }