FEATURE: Implement file drag-and-drop move functionality

b0esche_cloud/lib/repositories/http_file_repository.dart

@@ -49,7 +49,7 @@ class HttpFileRepository implements FileRepository {
     String sourcePath,
     String targetPath,
   ) async {
-    throw UnimplementedError();
+    await _fileService.moveFile(orgId, sourcePath, targetPath);
   }
 
   @override

b0esche_cloud/lib/services/file_service.dart

@@ -161,7 +161,16 @@ class FileService {
     String sourcePath,
     String targetPath,
   ) async {
-    throw UnimplementedError();
+    final response = await apiClient.post(
+      '/orgs/$orgId/files/move',
+      data: {
+        'sourcePath': sourcePath,
+        'targetPath': targetPath,
+      },
+    );
+    if (response.statusCode != 200) {
+      throw Exception('Failed to move file: ${response.statusCode}');
+    }
   }
 
   Future<void> renameFile(String orgId, String path, String newName) async {

go_cloud/internal/http/routes.go

@@ -190,6 +190,10 @@ func NewRouter(cfg *config.Config, db *database.DB, jwtManager *jwt.Manager, aut
 			r.With(middleware.Permission(db, auditLogger, permission.FileWrite)).Delete("/files", func(w http.ResponseWriter, req *http.Request) {
 				deleteOrgFileHandler(w, req, db, auditLogger, cfg)
 			})
+			// Move file/folder in org workspace (body: {"sourcePath":"/old", "targetPath":"/new"})
+			r.With(middleware.Permission(db, auditLogger, permission.FileWrite)).Post("/files/move", func(w http.ResponseWriter, req *http.Request) {
+				moveOrgFileHandler(w, req, db, auditLogger, cfg)
+			})
 			r.Route("/files/{fileId}", func(r chi.Router) {
 				r.With(middleware.Permission(db, auditLogger, permission.DocumentView)).Get("/view", func(w http.ResponseWriter, req *http.Request) {
 					viewerHandler(w, req, db, jwtManager, auditLogger)
@@ -1275,6 +1279,83 @@ func deleteOrgFilePostHandler(w http.ResponseWriter, r *http.Request, db *databa
 	deleteOrgFileHandler(w, r, db, auditLogger, cfg)
 }
 
+// moveOrgFileHandler moves/renames a file in org workspace
+func moveOrgFileHandler(w http.ResponseWriter, r *http.Request, db *database.DB, auditLogger *audit.Logger, cfg *config.Config) {
+	orgID := r.Context().Value(middleware.OrgKey).(uuid.UUID)
+	userIDStr, _ := middleware.GetUserID(r.Context())
+	userID, _ := uuid.Parse(userIDStr)
+
+	var req struct {
+		SourcePath string `json:"sourcePath"`
+		TargetPath string `json:"targetPath"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		errors.WriteError(w, errors.CodeInvalidArgument, "Bad request", http.StatusBadRequest)
+		return
+	}
+
+	// Get or create user's WebDAV client and move in Nextcloud
+	storageClient, err := getUserWebDAVClient(r.Context(), db, userID, cfg.NextcloudURL, cfg.NextcloudUser, cfg.NextcloudPass)
+	if err != nil {
+		errors.LogError(r, err, "Failed to get user WebDAV client (continuing with database move)")
+	} else {
+		sourceRel := strings.TrimPrefix(req.SourcePath, "/")
+		sourcePath := path.Join("/orgs", orgID.String(), sourceRel)
+		targetRel := strings.TrimPrefix(req.TargetPath, "/")
+		targetPath := path.Join("/orgs", orgID.String(), targetRel)
+		if err := storageClient.Move(r.Context(), sourcePath, targetPath); err != nil {
+			errors.LogError(r, err, "Failed to move in Nextcloud (continuing with database move)")
+		}
+	}
+
+	// Move in database: copy file with new path and delete old one
+	sourceFile, err := db.GetFileByPath(r.Context(), &orgID, nil, req.SourcePath)
+	if err != nil {
+		errors.LogError(r, err, "Failed to get source file")
+		errors.WriteError(w, errors.CodeInternal, "Server error", http.StatusInternalServerError)
+		return
+	}
+
+	// Determine new file name
+	var newPath string
+	if strings.HasSuffix(req.TargetPath, "/") {
+		// Moving into a folder
+		newPath = path.Join(req.TargetPath, sourceFile.Name)
+	} else {
+		// Moving/renaming to a specific path
+		newPath = req.TargetPath
+	}
+
+	// Create new file entry with updated path
+	movedFile := &database.File{
+		ID:       sourceFile.ID,
+		OrgID:    sourceFile.OrgID,
+		Path:     newPath,
+		Name:     path.Base(newPath),
+		Size:     sourceFile.Size,
+		MimeType: sourceFile.MimeType,
+		IsFolder: sourceFile.IsFolder,
+	}
+
+	// Update in database
+	if err := db.UpdateFile(r.Context(), movedFile); err != nil {
+		errors.LogError(r, err, "Failed to update file path")
+		errors.WriteError(w, errors.CodeInternal, "Server error", http.StatusInternalServerError)
+		return
+	}
+
+	auditLogger.Log(r.Context(), audit.Entry{
+		UserID:  &userID,
+		OrgID:   &orgID,
+		Action:  "move_file",
+		Success: true,
+	})
+
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(`{"status":"ok"}`))
+}
+
+
 // createUserFileHandler creates a file or folder record for the authenticated user's personal workspace.
 func createUserFileHandler(w http.ResponseWriter, r *http.Request, db *database.DB, auditLogger *audit.Logger, cfg *config.Config) {
 	userIDStr, ok := middleware.GetUserID(r.Context())