fix: skip canvas SSE fetch in chat shared page to eliminate spurious 103 error (#14190)

## What does this PR do?

Fixes the `hint : 103 Only owner of canvas authorized for this
operation` error that appears when opening a **Chat** shared link
(`/chats/share?shared_id=...&from=chat`).

## Root Cause

The Chat shared page (`web/src/pages/next-chats/share/index.tsx`)
unconditionally calls `useFetchFlowSSE()`, which requests
`/api/canvas/getsse/{sharedId}`. This is an Agent Canvas endpoint that
validates canvas ownership. When sharing a **Chat** dialog (not an
Agent):

1. `sharedId` is a `dialog_id`, not a `canvas_id`
2. The API token's `tenant_id` doesn't match any canvas owner
3. The backend returns `code: 103, message: "Only owner of canvas
authorized for this operation."`
4. The global error interceptor in `request.ts` displays it as a
notification: `hint : 103 Only owner of canvas authorized for this
operation.`

## Changes

- **`web/src/hooks/use-agent-request.ts`**: Added an `enabled` parameter
to `useFetchFlowSSE` so callers can conditionally skip the query.
- **`web/src/pages/next-chats/share/index.tsx`**: Only enable
`useFetchFlowSSE` when `from === SharedFrom.Agent`. For Chat shares, the
hook is disabled, avoiding the unnecessary canvas API call entirely.

## Related Issue

Closes #14115

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

---------

Signed-off-by: noob <yixiao121314@outlook.com>

web/src/pages/user-setting/data-source/data-source-detail-page/index.tsx

@@ -144,7 +144,7 @@ const SourceDetailPage = () => {
     ];
   }, [detail, runSchedule]);
 
-  const { addLoading, handleAddOk } = useAddDataSource({isEdit:true});
+  const { addLoading, handleAddOk } = useAddDataSource({ isEdit: true });
 
   const onSubmit = useCallback(() => {
     formRef?.current?.submit();

web/src/pages/user-setting/data-source/hooks.ts

@@ -3,7 +3,8 @@ import { useSetModalState } from '@/hooks/common-hooks';
 import { useGetPaginationWithRouter } from '@/hooks/logic-hooks';
 import dataSourceService, {
   dataSourceRebuild,
-  dataSourceResume, dataSourceUpdate,
+  dataSourceResume,
+  dataSourceUpdate,
   deleteDataSource,
   featchDataSourceDetail,
   getDataSourceLogs,
@@ -68,7 +69,7 @@ export const useListDataSource = () => {
   return { list, categorizedList: updatedDataSourceTemplates, isFetching };
 };
 
-export const useAddDataSource = ({isEdit=false}:{isEdit?:boolean} ) => {
+export const useAddDataSource = ({ isEdit = false }: { isEdit?: boolean }) => {
   const [addSource, setAddSource] = useState<IDataSorceInfo | undefined>(
     undefined,
   );