Keep remote agent status in sync after completion and approvals (#34729)

* fix(remote): reconcile stale paired agent status and pane titles

Adapt the remote completion repair from #25205 while preserving sparse runtime pane slots through existing PTY bindings.

Co-authored-by: Manan Chataut <mananchataut@gmail.com>

* fix(remote): preserve pane identity when reconciling moved titles

Use mounted manager identities and retained PTY bindings ahead of replay order; keep fresh byte-stream ownership on the correct moved pane.

* fix(remote): release byte status fence after host approval

* fix(remote): tighten paired title removal and test the timing fence

- Share the byte-write timing decision (resolveRendererOwnedAgentStatusTiming) between pty-connection and the flap test so reverting it fails a test.
- Only delete a saved pane title when its durable leaf is absent from both the host layout and local panes; unresolved or surface-less slots are kept.
- Share the client-fence predicate (clientAgentStatusFencesHost) between status and title reconciliation.
- Cover removed-leaf spinner fallback in worktree status and a client split absent from a pre-split host snapshot.

* fix(remote): correct fence predicate and title test types

---------

Co-authored-by: Manan Chataut <mananchataut@gmail.com>

src/shared/runtime-pane-title-leaf-id.test.ts

@@ -1,6 +1,7 @@
 import { describe, expect, it } from 'vitest'
 import type { TerminalLayoutSnapshot } from './terminal-tab-types'
 import {
+  isRuntimePaneTitleOrphan,
   resolveRuntimePaneTitleForLeaf,
   resolveRuntimePaneTitleLeafResolution
 } from './runtime-pane-title-leaf-id'
@@ -60,3 +61,16 @@ describe('resolveRuntimePaneTitleLeafResolution', () => {
     })
   })
 })
+
+describe('isRuntimePaneTitleOrphan', () => {
+  it('never treats numeric slots as removed panes', () => {
+    for (const runtimePaneId of ['0', '-1', '2', '3']) {
+      expect(isRuntimePaneTitleOrphan(runtimePaneId, new Set([LEAF_A]))).toBe(false)
+    }
+  })
+
+  it('flags only a durable leaf id the layout no longer has', () => {
+    expect(isRuntimePaneTitleOrphan(LEAF_B, new Set([LEAF_A, LEAF_B]))).toBe(false)
+    expect(isRuntimePaneTitleOrphan(LEAF_B, new Set([LEAF_A]))).toBe(true)
+  })
+})

src/shared/runtime-pane-title-leaf-id.ts

@@ -125,6 +125,14 @@ export function resolveRuntimePaneTitleLeafIdFromRoot(
   return leafIds[numericPaneId - FIRST_PANE_ID] ?? null
 }
 
+/** Numeric slots survive pane closes with gaps, so only absent durable leaf ids prove removal. */
+export function isRuntimePaneTitleOrphan(
+  runtimePaneId: string,
+  layoutLeafIds: ReadonlySet<string>
+): boolean {
+  return isTerminalLeafId(runtimePaneId) && !layoutLeafIds.has(runtimePaneId)
+}
+
 /**
  * Resolve a sparse live runtime pane slot through the tab's current PTY bindings.
  * PaneManager ids survive closes with gaps, while the live PTY list retains order.