refactor(util): move response helper to common/response and session logic to oauth

- Relocated generic HTTP response helpers (Response, OK, Err, etc.) from internal/util/ to a dedicated internal/common/response/ package.
- Renamed ResponseAny to Any to resolve revive stuttering warnings.
- Moved session building options and cookie headers logic from internal/util/ to internal/apps/oauth/.
- Removed all direct imports of Gin/Sessions/HTTP frameworks from internal/util/ to keep general utilities 100% pure.
- Regenerated Swagger API documentation via make swagger.
- All tests and make code-check compile and pass with 0 issues.

internal/apps/admin/auth_source/routers_test.go

@@ -4,8 +4,7 @@
 
 package auth_source
 
-import (
-	"bytes"
+import ("bytes"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -16,7 +15,8 @@ import (
 	"github.com/Rain-kl/Wavelet/internal/testhelper"
 	"github.com/Rain-kl/Wavelet/internal/util"
 	"github.com/gin-gonic/gin"
-)
+
+	"github.com/Rain-kl/Wavelet/internal/common/response")
 
 func setupTestRouter(authUser *model.User) *gin.Engine {
 	gin.SetMode(gin.TestMode)
@@ -67,7 +67,7 @@ func TestListAuthSources(t *testing.T) {
 		t.Errorf("expected 200 OK, got %d", w.Code)
 	}
 
-	var resp util.ResponseAny
+	var resp response.Any
 	_ = json.Unmarshal(w.Body.Bytes(), &resp)
 
 	dataBytes, _ := json.Marshal(resp.Data)