type(github): propagate readonly workItemsCache through TaskPage

Widen fetchWorkItems, inflight promises, and TaskPage cache selectors
so CacheEntry<readonly GitHubWorkItem[]> typechecks against consumers.

Co-authored-by: Orca <help@stably.ai>

src/renderer/src/components/task-page-cache-selectors.ts

@@ -43,7 +43,7 @@ export type TaskPageWorkItemsFetchOptions = {
   noCache: boolean
 }
 
-type WorkItemsCache = Record<string, CacheEntry<GitHubWorkItem[]>>
+type WorkItemsCache = Record<string, CacheEntry<readonly GitHubWorkItem[]>>
 export type TaskPageWorkItemPages = readonly (GitHubWorkItem[] | null)[]
 
 export function deriveTaskPageGitHubWorkItemsFetchOptions(
@@ -61,7 +61,7 @@ export function selectTaskPageWorkItemsCacheEntries(
   repos: readonly TaskPageRepoCacheInput[],
   limit: number,
   query: string
-): (CacheEntry<GitHubWorkItem[]> | undefined)[] {
+): (CacheEntry<readonly GitHubWorkItem[]> | undefined)[] {
   return repos.map(
     (repo) =>
       workItemsCache[
@@ -72,7 +72,7 @@ export function selectTaskPageWorkItemsCacheEntries(
 
 export function buildTaskPageRepoSourceState(
   repos: readonly TaskPageRepoCacheInput[],
-  entries: readonly (CacheEntry<GitHubWorkItem[]> | undefined)[]
+  entries: readonly (CacheEntry<readonly GitHubWorkItem[]> | undefined)[]
 ): TaskPageRepoSourceState[] {
   return repos.map((repo, index) => {
     const entry = entries[index]
@@ -126,7 +126,7 @@ function taskPageWorkItemCacheKey(item: GitHubWorkItem): string {
 
 export function reconcileTaskPagePagesWithWorkItemsCache(
   pages: TaskPageWorkItemPages,
-  entries: readonly (CacheEntry<GitHubWorkItem[]> | undefined)[]
+  entries: readonly (CacheEntry<readonly GitHubWorkItem[]> | undefined)[]
 ): (GitHubWorkItem[] | null)[] {
   const cachedItems = new Map<string, GitHubWorkItem>()
   for (const entry of entries) {

src/renderer/src/store/slices/github.ts

@@ -685,7 +685,7 @@ type InflightChecks = {
 const inflightChecksRequests = new Map<string, InflightChecks>()
 const inflightCommentsRequests = new Map<string, Promise<PRComment[]>>()
 type InflightWorkItems = {
-  promise: Promise<GitHubWorkItem[]>
+  promise: Promise<readonly GitHubWorkItem[]>
   force: boolean
   noCache: boolean
   requireComplete: boolean
@@ -1974,7 +1974,7 @@ export type GitHubSlice = {
     limit: number,
     query: string,
     options?: FetchOptions
-  ) => Promise<GitHubWorkItem[]>
+  ) => Promise<readonly GitHubWorkItem[]>
   /**
    * Fan out one work-item query across repos; partial failures don't reject — a repo with no cached fallback increments `failedCount`, but one served stale cache on rejection isn't counted.
    * `githubUnavailable`: every selected GitHub source refresh failed because GitHub was unreachable (5xx/network/rate-limit), even if stale cache remains — lets the caller attribute the stale/empty list.
@@ -2658,7 +2658,13 @@ export const createGitHubSlice: StateCreator<AppState, [], [], GitHubSlice> = (s
     return null
   },
 
-  fetchWorkItems: async (repoId, repoPath, limit, query, options): Promise<GitHubWorkItem[]> => {
+  fetchWorkItems: async (
+    repoId,
+    repoPath,
+    limit,
+    query,
+    options
+  ): Promise<readonly GitHubWorkItem[]> => {
     if (isGitHubWorkItemsQueryTooLarge(query)) {
       return []
     }