Add 'Has Workspace' mode to show Linear issues linked to local worktrees (#12632)

* feat(linear): add 'Has Workspace' mode to show issues linked to local wo

Enable users to view and open existing workspaces attached to Linear issues
instead of accidentally starting duplicates. Includes shared worktree attachment
labeling for consistent UX across GitHub and Linear surfaces.

* fix(linear): apply search filter in 'in-orca' mode to prevent drops

- Apply search filter in 'in-orca' mode even without active context label to prevent
  team filters from silently hiding linked tickets (no "Fetch more" recovery path)
- Add aria-label to workspace-open button for accessibility
- Update tooltip from "local worktree" to "Orca workspace"
- Reorganize i18n: move workspace.open from lib.linear to components.issue
- Expand test coverage for workspace start and activation scenarios

* fix(linear): avoid mutating in-orca linked refs during render

React Doctor fails static analysis when refs are written during render.
Keep the latest linked refs in an effect so the in-orca loader can still
read them without re-running on identity-only worktree churn.

src/shared/types.ts

@@ -3317,7 +3317,7 @@ export type TaskResumeState = {
   githubItemsPreset?: TaskViewPresetId | null
   githubItemsQuery?: string
   githubProjectHiddenFieldIdsByView?: Record<string, string[]>
-  linearMode?: 'issues' | 'projects' | 'views'
+  linearMode?: 'issues' | 'projects' | 'views' | 'in-orca'
   linearPreset?: 'assigned' | 'created' | 'all' | 'completed'
   linearQuery?: string
   linearContext?: {