Follow the tool's credential mode in the share dialog once it loads

The dialog read the mode once, so opening Share before the connections
loaded showed owner mode for a member-mode tool and ignored a forced
mode.

frontend/src/teams/ShareToTeamModal.test.tsx

@@ -477,6 +477,17 @@ describe('ShareToTeamModal credentials', () => {
     expect(text()).toContain('settings.connectors.share.forced');
   });
 
+  it('follows the mode once the connection loads after opening', async () => {
+    await render();
+    await render(credentials({ hasWrites: true, mode: 'member' }));
+    expect(toggle('member').getAttribute('aria-checked')).toBe('true');
+    // Member mode runs on each member's own account: nothing to confirm.
+    expect(body().querySelector('#share-confirm-writes')).toBeNull();
+    await render(credentials({ hasWrites: true, forcedMode: 'owner' }));
+    expect(toggle('owner').getAttribute('aria-checked')).toBe('true');
+    expect(toggle('member').disabled).toBe(true);
+  });
+
   describe('access settings of a connected tool', () => {
     const toolSettings = (values: Record<string, boolean> = {}) => ({
       success: true,

frontend/src/teams/ShareToTeamModal.tsx

@@ -157,9 +157,19 @@ export default function ShareToTeamModal({
   const [loadError, setLoadError] = useState(false);
   const [actionError, setActionError] = useState<string | null>(null);
 
+  const savedCredentialMode =
+    credentials?.forcedMode ?? credentials?.mode ?? 'owner';
   const [credentialMode, setCredentialMode] = useState<'owner' | 'member'>(
-    credentials?.forcedMode ?? credentials?.mode ?? 'owner',
+    savedCredentialMode,
   );
+  // The caller may open the dialog before the tool's connection has loaded:
+  // follow the mode (or an admin's forced one) when it arrives or changes.
+  const [seenCredentialMode, setSeenCredentialMode] =
+    useState(savedCredentialMode);
+  if (savedCredentialMode !== seenCredentialMode) {
+    setSeenCredentialMode(savedCredentialMode);
+    setCredentialMode(savedCredentialMode);
+  }
   const [writesConfirmed, setWritesConfirmed] = useState(false);
   const needsWriteConfirm =
     !!credentials && credentialMode === 'owner' && credentials.hasWrites;