fix(tasks): key pagination resets on repo selection, not array identity

The repos store installs a fresh array on every repos:changed event, so
the pagination-reset effect fired on background refreshes and bumped the
request generation, silently discarding any in-flight page navigation —
clicking an unloaded page did nothing whenever a repo refresh landed
during the fetch. Key the effect on the stable selection string instead.

src/renderer/src/components/TaskPage.tsx

@@ -3205,6 +3205,17 @@ export default function TaskPage(): React.JSX.Element {
     [eligibleRepos, repoSelection]
   )
 
+  // Why: stable string key for selectedRepos — the repos store installs a fresh
+  // array on every repos:changed event, so array-identity deps re-fire even when
+  // the selection is unchanged.
+  const selectedReposKey = useMemo(
+    () =>
+      selectedRepos
+        .map((r) => `${r.id}|${r.path}|${r.connectionId ?? ''}|${r.executionHostId ?? ''}`)
+        .join(','),
+    [selectedRepos]
+  )
+
   // Why: many affordances need *a* repo; use the first selected as default, while cross-repo dialogs still let the user override per-action.
   const primaryRepo = selectedRepos[0] ?? null
   const linearWorkspaces = linearStatus.workspaces ?? []
@@ -3810,11 +3821,14 @@ export default function TaskPage(): React.JSX.Element {
   const fetchWorkItemsNextPage = useAppStore((s) => s.fetchWorkItemsNextPage)
   const countWorkItemsAcrossRepos = useAppStore((s) => s.countWorkItemsAcrossRepos)
 
+  // Why: keyed on selectedReposKey, not the selectedRepos array — a background
+  // repos:changed refresh mid-flight would otherwise bump the generation and
+  // silently discard the user's page navigation (#11485).
   useEffect(() => {
     paginationGenerationRef.current += 1
     setPaginationLoading(false)
     setLoadingTargetPage(null)
-  }, [selectedRepos, appliedTaskSearch, workItemsInvalidationNonce])
+  }, [selectedReposKey, appliedTaskSearch, workItemsInvalidationNonce])
 
   // Why: the dialog's "Use" button routes through the same direct-launch flow as the row-level "Use" CTA so behavior is consistent regardless of entry point.
   const githubTaskDrawerWorkItem = useAppStore((s) => s.githubTaskDrawerWorkItem)
@@ -4829,15 +4843,6 @@ export default function TaskPage(): React.JSX.Element {
     jiraTaskSourceContext
   ])
 
-  // Why: stable string key for selectedRepos so the GitLab effect doesn't re-run on every parent render from a new array ref.
-  const selectedReposKey = useMemo(
-    () =>
-      selectedRepos
-        .map((r) => `${r.id}|${r.path}|${r.connectionId ?? ''}|${r.executionHostId ?? ''}`)
-        .join(','),
-    [selectedRepos]
-  )
-
   // Why: fetch GitLab Issues and MRs separately so errors stay isolated per tab (mirrors GitHub's split endpoints).
   useEffect(() => {
     if (taskSource !== 'gitlab') {