feat(devices): 设备默认名「平台简写·主机名」+ 支持重命名(1.0.13)

① 默认名:DeviceIdentity 改「平台简写(Win/Mac/Linux/iOS/Andr)·主机名」,主机名截
   到 8、总长≈12(替代裸主机名,更短)。
② 重命名:新端点 POST /v1/me/devices/{uuid}/rename(Service.RenameDevice 校验归属+
   截 64);store.UpdateName;客户端 account_api.renameDevice + provider.rename +
   「我的设备」⋯ 菜单加「重命名」+ 输入弹窗;l10n(zh/en)。
③ 版本 1.0.13。
测试:server RenameDevice(归属/空名/404)+ 客户端 rename widget;全量 go/flutter 绿。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/internal/devices/handler.go

@@ -28,6 +28,7 @@ func (h *Handler) RegisterRoutes(r chi.Router) {
 	r.Get("/devices", h.ListDevices)
 	r.Delete("/devices/{id}", h.DeleteDevice)
 	r.Post("/devices/{id}/logout", h.ForceLogout)
+	r.Post("/devices/{id}/rename", h.RenameDevice)
 }
 
 type listDevicesResponse struct {
@@ -87,3 +88,25 @@ func (h *Handler) ForceLogout(w http.ResponseWriter, r *http.Request) {
 
 	w.WriteHeader(http.StatusNoContent)
 }
+
+// RenameDevice handles POST /v1/me/devices/{id}/rename — set a device's name.
+func (h *Handler) RenameDevice(w http.ResponseWriter, r *http.Request) {
+	userID, ok := auth.UserIDFromContext(r.Context())
+	if !ok {
+		apierr.WriteJSON(w, http.StatusUnauthorized, apierr.ErrUnauthorized)
+		return
+	}
+	var req struct {
+		Name string `json:"name"`
+	}
+	if err := json.NewDecoder(http.MaxBytesReader(w, r.Body, 1<<14)).Decode(&req); err != nil {
+		apierr.WriteJSON(w, http.StatusBadRequest, apierr.ErrBadRequest)
+		return
+	}
+	deviceUUID := chi.URLParam(r, "id")
+	if apiErr := h.svc.RenameDevice(r.Context(), userID, deviceUUID, req.Name); apiErr != nil {
+		apierr.WriteJSON(w, StatusForError(apiErr), apiErr)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}