feat(web-client-tpos): add BFF staff endpoint for admin staff directory

apps/web-client-tpos-net/src/WebClientTpos.Server/Controllers/BffDataController.cs

@@ -54,6 +54,24 @@ public class BffDataController : ControllerBase
         return Ok(shop);
     }
 
+    [HttpGet("staff")]
+    public async Task<IActionResult> GetStaff()
+    {
+        await using var conn = new NpgsqlConnection(ConnStr("merchant_service"));
+        var staff = await conn.QueryAsync<dynamic>(
+            @"SELECT ms.id, ms.user_id, ms.employee_code, ms.phone, ms.email,
+                     ms.joined_at, ms.terminated_at,
+                     sr.name as role, ss.name as status,
+                     s.name as shop_name
+              FROM merchant_staff ms
+              JOIN staff_roles sr ON ms.role_id = sr.id
+              JOIN staff_statuses ss ON ms.status_id = ss.id
+              LEFT JOIN shop_members sm ON sm.staff_id = ms.id
+              LEFT JOIN shops s ON sm.shop_id = s.id
+              ORDER BY ms.joined_at DESC");
+        return Ok(staff);
+    }
+
     [HttpGet("shops/{shopId}/products")]
     public async Task<IActionResult> GetProducts(Guid shopId)
     {