Sidebar: land the switch-on fixes from the flip branch on main, switch still off (#31466)

* fix(sidebar): land flip-a's switch-on fixes on main, still dark (no flip)

The fixes found while the sidebar ran from main's feed, without turning
that on: ORCA_SIDEBAR_INPUTS_IS_MAIN stays false, and none of flip-a's
stop-gaps come along.

- Main stops counting a closed tab's terminal once it was asked to stop
  and no pane shows it; a failed or refused stop takes the request back,
  and a host out of contact stays unverifiable.
- Main fetches a paired server's rows with the transport's normal bound,
  so a server slower than 5 s still lists.
- A deferred unread raise flips the folder row it was decided for, and a
  read while the owner check is out cancels it.
- Phone: no worktree.ps flash before the feed; a host's last installed
  feed stands in while a fresh read is out; it highlights its own
  last-opened workspace and a fold never scrolls; projects file under
  their project group with the desktop's indent; the collapse spinner
  shows only after 500 ms; "Reopen to update" keeps the rows on screen.
- e2e helpers and journeys for the switch-on suite.

* fix(sidebar): keep an owed relay stop marked, clear a thrown stop, and prune pending unread raises

- A stop-and-wait that throws takes its stop request back, like one that fails.
- A final stop the legacy relay still owes stays marked, since the relay retries it.
- Pending unread raises are tracked only while one waits, so the map no longer grows.
- The paired-server fallback poll test gives its third fetch a reply and asserts live.

mobile/src/components/WorktreeListRow.tsx

@@ -9,6 +9,7 @@ import type { WorktreeCardDetails } from '../../../src/shared/worktree/card-prop
 import { isRemoteExecutionHostId } from '../../../src/shared/execution-host'
 import type { AgentActivityDisplayMode } from '../../../src/shared/ui-chrome-types'
 import { areStructurallyEqual } from '../worktree/structural-equality'
+import { projectGroupRowIndent } from '../worktree/project-group-indent'
 import { getWorktreeMetaGlyphPresence } from '../worktree/worktree-meta-glyph-presence'
 import { AgentSpinner } from './AgentSpinner'
 import { HostKindIcon } from './HostKindIcon'
@@ -64,6 +65,7 @@ function WorktreeListRowComponent({
   const folderMeta = item.comment?.trim() || item.path || 'Folder'
   const metaText = isFolderWorkspace ? folderMeta : displayBranch(item.branch)
   const lineageDepth = Math.max(0, item.lineageDepth ?? 0)
+  const indent = projectGroupRowIndent(item) + lineageDepth * 18
   const lineageChildCount = item.lineageChildCount ?? 0
   const shouldHideRepo = hideRepo && !item.showProjectName
   const showRepoChip = cardDetails.repoInTitle && !shouldHideRepo && !isFolderWorkspace
@@ -79,7 +81,7 @@ function WorktreeListRowComponent({
     <Pressable
       style={({ pressed }) => [
         styles.worktreeRow,
-        lineageDepth > 0 && { paddingLeft: spacing.lg + lineageDepth * 18 },
+        indent > 0 && { paddingLeft: spacing.lg + indent },
         item.isActive && styles.worktreeRowActive,
         pressed && styles.worktreeRowPressed
       ]}