fix(ssh): fold in partition tabs on demand, not only at startup

The ssh:<target> plane is LIVE — the CLI and headless surfaces still write it —
but the hoist ran only in the Store constructor. A tab created there mid-session
never reached local, so a reattach refused it as noTab and its shell ran on
unbound with the tab invisible until the app restarted. Same defect class as the
original report, with a narrower window.

The reattach now re-hoists once on a noTab refusal and retries the bind before
concluding no pane owns the shell. No polling, and it costs nothing on the path
where local already knows the tab.

Mutation-proofed: making the on-demand hoist a no-op reddens the new test.

src/main/persistence.ts

@@ -6590,6 +6590,25 @@ export class Store {
     return normalizeExecutionHostId(hostId) ?? LOCAL_EXECUTION_HOST_ID
   }
 
+  /**
+   * Re-run the partition hoist against current state.
+   *
+   * Why this is not construction-only: `ssh:<target>` is a LIVE plane. A tab the CLI or a headless
+   * surface creates mid-session lands there, `local` never learns of it, and a reattach then
+   * refuses it as `noTab` — the shell runs on unbound and its tab stays invisible until the app
+   * restarts. Re-hoisting on that refusal closes the window without polling.
+   */
+  hoistSshPartitionsNow(): boolean {
+    const changed = hoistSshPartitionsIntoLocalSession(
+      this.state,
+      this.state.workspaceSessionsByHostId
+    )
+    if (changed) {
+      this.scheduleSave()
+    }
+    return changed
+  }
+
   /** Read once, immediately after a refused `persistPtyBinding`. Clearing on read keeps a stale
    *  reason from being attributed to a later call that never set one. */
   consumePtyBindingRefusalReason(): PtyBindingRefusalReason | undefined {

src/main/ssh-partition-upgrade-tab-loss.test.ts

@@ -439,4 +439,40 @@ describe('an SSH pane whose membership was persisted into the ssh partition', ()
       'a local-only layout edit reached through into the ssh partition'
     ).toBe(PTY)
   })
+
+  // `ssh:<target>` is a LIVE plane: the CLI and headless surfaces still write it. A tab created
+  // there mid-session is not in `local`, so a reattach refuses it as noTab and its shell runs on
+  // unbound. Re-hoisting on demand closes that window without waiting for a restart.
+  it('folds in a tab the partition gained mid-session, without a restart', async () => {
+    const before = await createStore()
+    before.setWorkspaceSession(paneSession() as never, SSH_PARTITION)
+    before.flushOrThrow()
+    stripHoistMarker()
+
+    const store = await reopenStore()
+    expect(store.getWorkspaceSession().tabsByWorktree?.[WORKTREE] ?? []).toHaveLength(1)
+
+    // The CLI adds a pane to the partition while the app is running.
+    const grown = paneSession()
+    grown.tabsByWorktree[WORKTREE] = [
+      ...grown.tabsByWorktree[WORKTREE],
+      { ...grown.tabsByWorktree[WORKTREE][0], id: 'tab-cli' }
+    ]
+    grown.terminalLayoutsByTabId = {
+      ...grown.terminalLayoutsByTabId,
+      'tab-cli': {
+        root: { type: 'leaf' as const, leafId: LEAF_TWO },
+        activeLeafId: LEAF_TWO,
+        expandedLeafId: null,
+        ptyIdsByLeafId: { [LEAF_TWO]: PTY }
+      }
+    } as typeof grown.terminalLayoutsByTabId
+    store.setWorkspaceSession(grown as never, SSH_PARTITION)
+
+    expect(store.hoistSshPartitionsNow(), 'the on-demand hoist reported no change').toBe(true)
+    expect(
+      (store.getWorkspaceSession().tabsByWorktree?.[WORKTREE] ?? []).map((tab) => tab.id).sort(),
+      'a tab the partition gained mid-session stayed invisible until restart'
+    ).toEqual(['tab-1', 'tab-cli'])
+  })
 })

src/main/ssh/ssh-relay-session.ts

@@ -2618,6 +2618,21 @@ export class SshRelaySession {
       } catch (error) {
         console.error('[ssh-relay-session] Failed to persist reconnect incarnation:', error)
       }
+      if (bind?.bound === false && bind.refusalReason === 'noTab') {
+        // The partition is a live plane, so a tab created there mid-session is not in `local` yet.
+        // Fold it in and try once more before concluding no pane owns this shell.
+        if (this.store?.hoistSshPartitionsNow()) {
+          bind = bindPaneShell({
+            store: this.store,
+            worktreeId: lease.worktreeId,
+            tabId,
+            leafId: lease.leafId,
+            ptyId: appPtyId,
+            mayCreate: false,
+            ...(incarnationId ? { incarnationId } : {})
+          })
+        }
+      }
       if (bind?.bound === false && bind.refusalReason === 'noTab') {
         // No durable tab owns this leaf, so there is nothing to publish it against — registering
         // would announce a pane that does not exist. Unresolved, not dead: the shell keeps running