fix(native-chat): bring the structured core branch back under max-lines (#15168)

Static analysis was red on the branch itself, which is why every stacked PR
inherited three failing checks. Two files were over their caps, both from this
branch's own growth:

- `use-app-startup-hydration.ts` (307/300): the startup store subscription moves
  to `use-app-startup-actions.ts`. It is a separate concern from the boot chain
  and was the only reason the file needed `useShallow`.
- the mobile session route (5036/5015): the structured chat view was wired
  inline with eighteen props. It moves to `MobileStructuredSessionPane`, so the
  route passes one entry object.

No per-file cap was raised and no rule was disabled.

Verified: repo-wide oxlint clean (0 errors, 15765 files), web typecheck, mobile
typecheck, and the startup source-slice suite (25 tests).

mobile/app/h/[hostId]/session/[worktreeId].tsx

@@ -228,7 +228,7 @@ import {
 } from '../../../../src/dictation/mobile-dictation-setup'
 import { TerminalPaneView } from '../../../../src/session/TerminalPaneView'
 import { MobileNativeChatOverlay } from '../../../../src/session/MobileNativeChatOverlay'
-import { MobileStructuredAgentSessionView } from '../../../../src/session/MobileStructuredAgentSessionView'
+import { MobileStructuredSessionPane } from '../../../../src/session/MobileStructuredSessionPane'
 import { MobileStructuredSessionCreateError } from '../../../../src/session/MobileStructuredSessionCreateError'
 import { useMobileStructuredSessionEntry } from '../../../../src/session/use-mobile-structured-session-entry'
 import { showMobileStructuredChatChoice } from '../../../../src/session/mobile-structured-session-create'
@@ -4684,36 +4684,10 @@ export default function SessionScreen() {
                 )}
               </View>
             ) : activeStructuredTab ? (
-              <MobileStructuredAgentSessionView
+              <MobileStructuredSessionPane
                 key={activeStructuredTab.sessionId}
-                items={structuredSessionEntry.session.items}
-                status={structuredSessionEntry.session.status}
-                error={structuredSessionEntry.session.error}
-                hasOlder={structuredSessionEntry.session.hasOlder}
-                loadingOlder={structuredSessionEntry.session.loadingOlder}
-                onLoadOlder={structuredSessionEntry.session.loadOlder}
+                entry={structuredSessionEntry}
                 onOpenFile={handleNativeChatFileTap}
-                outbox={structuredSessionEntry.writes.outbox}
-                writeError={structuredSessionEntry.writes.error}
-                onSend={async (text, restored) => {
-                  const accepted = await structuredSessionEntry.writes.send(text, [
-                    ...restored,
-                    ...structuredSessionEntry.attachments.attachments
-                  ])
-                  if (accepted) {
-                    structuredSessionEntry.attachments.clear()
-                  }
-                  return accepted
-                }}
-                onTakeQueuedForEdit={structuredSessionEntry.writes.takeQueuedForEdit}
-                onRetry={structuredSessionEntry.writes.retry}
-                onRespondToPrompt={structuredSessionEntry.writes.respondToPrompt}
-                sessionOptions={structuredSessionEntry.sessionOptions}
-                attachments={structuredSessionEntry.attachments.attachments}
-                isAttaching={structuredSessionEntry.attachments.attaching}
-                onAttachImage={() => void structuredSessionEntry.attachments.attach('library')}
-                onRemoveAttachment={structuredSessionEntry.attachments.remove}
-                onCancel={structuredSessionEntry.writes.cancel}
               />
             ) : activePendingTerminalTab ? (
               <View style={styles.emptyState}>

mobile/src/session/MobileStructuredSessionPane.tsx

@@ -0,0 +1,46 @@
+// Wires one structured agent session entry into the chat view. Kept out of the
+// session route so the route threads one object instead of eighteen props.
+
+import { MobileStructuredAgentSessionView } from './MobileStructuredAgentSessionView'
+import type { useMobileStructuredSessionEntry } from './use-mobile-structured-session-entry'
+
+type StructuredSessionEntry = ReturnType<typeof useMobileStructuredSessionEntry>
+
+export function MobileStructuredSessionPane({
+  entry,
+  onOpenFile
+}: {
+  entry: StructuredSessionEntry
+  onOpenFile: (path: string, line?: number) => void
+}) {
+  const { session, writes, attachments, sessionOptions } = entry
+  return (
+    <MobileStructuredAgentSessionView
+      items={session.items}
+      status={session.status}
+      error={session.error}
+      hasOlder={session.hasOlder}
+      loadingOlder={session.loadingOlder}
+      onLoadOlder={session.loadOlder}
+      onOpenFile={onOpenFile}
+      outbox={writes.outbox}
+      writeError={writes.error}
+      onSend={async (text, restored) => {
+        const accepted = await writes.send(text, [...restored, ...attachments.attachments])
+        if (accepted) {
+          attachments.clear()
+        }
+        return accepted
+      }}
+      onTakeQueuedForEdit={writes.takeQueuedForEdit}
+      onRetry={writes.retry}
+      onRespondToPrompt={writes.respondToPrompt}
+      sessionOptions={sessionOptions}
+      attachments={attachments.attachments}
+      isAttaching={attachments.attaching}
+      onAttachImage={() => void attachments.attach('library')}
+      onRemoveAttachment={attachments.remove}
+      onCancel={writes.cancel}
+    />
+  )
+}

src/renderer/src/app-shell/use-app-startup-actions.ts

@@ -0,0 +1,39 @@
+// The renderer boot chain's store subscription, kept apart from the chain itself
+// so one useShallow equality check covers every startup action.
+
+import { useShallow } from 'zustand/react/shallow'
+import { useAppStore } from '../store'
+
+export function useStartupActions() {
+  // Why: consolidate action refs into one useShallow subscription so React runs one equality check per store mutation instead of one per action.
+  return useAppStore(
+    useShallow((s) => ({
+      fetchReposForAllHosts: s.fetchReposForAllHosts,
+      awaitLocalRepoCatalogSettlement: s.awaitLocalRepoCatalogSettlement,
+      fetchProjectGroupsForAllHosts: s.fetchProjectGroupsForAllHosts,
+      fetchFolderWorkspacesForAllHosts: s.fetchFolderWorkspacesForAllHosts,
+      fetchAllWorktrees: s.fetchAllWorktrees,
+      fetchWorktrees: s.fetchWorktrees,
+      fetchWorktreeLineage: s.fetchWorktreeLineage,
+      fetchOrcaProfiles: s.fetchOrcaProfiles,
+      fetchSettings: s.fetchSettings,
+      awaitOwnerWorktreeVisibilityDefaultsHydration:
+        s.awaitOwnerWorktreeVisibilityDefaultsHydration,
+      fetchKeybindings: s.fetchKeybindings,
+      initGitHubCache: s.initGitHubCache,
+      hydrateWorkspaceSession: s.hydrateWorkspaceSession,
+      hydrateTabsSession: s.hydrateTabsSession,
+      hydrateEditorSession: s.hydrateEditorSession,
+      hydrateBrowserSession: s.hydrateBrowserSession,
+      fetchBrowserSessionProfiles: s.fetchBrowserSessionProfiles,
+      reconnectPersistedTerminals: s.reconnectPersistedTerminals,
+      setTerminalStartupRestorationReady: s.setTerminalStartupRestorationReady,
+      setDeferredSshReconnectTargets: s.setDeferredSshReconnectTargets,
+      setSshConnectionState: s.setSshConnectionState,
+      hydratePersistedUI: s.hydratePersistedUI,
+      setHydrationSucceeded: s.setHydrationSucceeded,
+      pruneLastVisitedTimestamps: s.pruneLastVisitedTimestamps,
+      seedActiveWorktreeLastVisitedIfMissing: s.seedActiveWorktreeLastVisitedIfMissing
+    }))
+  )
+}

src/renderer/src/app-shell/use-app-startup-hydration.ts

@@ -1,8 +1,8 @@
 import { useEffect, useRef } from 'react'
-import { useShallow } from 'zustand/react/shallow'
 import { syncZoomCSSVar } from '@/lib/ui-zoom'
 import { installCodexDetachedPaneRestartExecutor } from '@/components/terminal-pane/codex-detached-pane-restart-scheduler'
 import { useAppStore } from '../store'
+import { useStartupActions } from './use-app-startup-actions'
 import { WORKTREE_REFRESH_CONCURRENCY } from '../store/slices/worktrees'
 import { sweepRestoredCodexPanesForStaleAccounts } from '../lib/codex-stale-pane-sweep'
 import { fetchWorkspaceSessionWithRuntimeHostOwners } from '../lib/workspace-session-host-persistence'
@@ -46,40 +46,6 @@ async function listRuntimeSessionHostIdsForStartup(): Promise<ExecutionHostId[]>
   }
 }
 
-function useStartupActions() {
-  // Why: consolidate action refs into one useShallow subscription so React runs one equality check per store mutation instead of one per action.
-  return useAppStore(
-    useShallow((s) => ({
-      fetchReposForAllHosts: s.fetchReposForAllHosts,
-      awaitLocalRepoCatalogSettlement: s.awaitLocalRepoCatalogSettlement,
-      fetchProjectGroupsForAllHosts: s.fetchProjectGroupsForAllHosts,
-      fetchFolderWorkspacesForAllHosts: s.fetchFolderWorkspacesForAllHosts,
-      fetchAllWorktrees: s.fetchAllWorktrees,
-      fetchWorktrees: s.fetchWorktrees,
-      fetchWorktreeLineage: s.fetchWorktreeLineage,
-      fetchOrcaProfiles: s.fetchOrcaProfiles,
-      fetchSettings: s.fetchSettings,
-      awaitOwnerWorktreeVisibilityDefaultsHydration:
-        s.awaitOwnerWorktreeVisibilityDefaultsHydration,
-      fetchKeybindings: s.fetchKeybindings,
-      initGitHubCache: s.initGitHubCache,
-      hydrateWorkspaceSession: s.hydrateWorkspaceSession,
-      hydrateTabsSession: s.hydrateTabsSession,
-      hydrateEditorSession: s.hydrateEditorSession,
-      hydrateBrowserSession: s.hydrateBrowserSession,
-      fetchBrowserSessionProfiles: s.fetchBrowserSessionProfiles,
-      reconnectPersistedTerminals: s.reconnectPersistedTerminals,
-      setTerminalStartupRestorationReady: s.setTerminalStartupRestorationReady,
-      setDeferredSshReconnectTargets: s.setDeferredSshReconnectTargets,
-      setSshConnectionState: s.setSshConnectionState,
-      hydratePersistedUI: s.hydratePersistedUI,
-      setHydrationSucceeded: s.setHydrationSucceeded,
-      pruneLastVisitedTimestamps: s.pruneLastVisitedTimestamps,
-      seedActiveWorktreeLastVisitedIfMissing: s.seedActiveWorktreeLastVisitedIfMissing
-    }))
-  )
-}
-
 /**
  * Runs the renderer's one-shot boot chain: settings, persisted UI, the local repo catalog,
  * the workspace session, SSH reconnect, and terminal restoration — then unlocks the session