* Rebase stacks onto the latest remote trunk

Fetch the configured trunk explicitly before sync or rebase and use that
fetched ref whenever the local trunk cannot be safely updated, while
preserving local-only and locally-ahead trunks. Fail instead of reporting
success when the fetch or rebase never starts, carry the resolved trunk
through conflict recovery, and verify the resulting ancestry before sync
pushes or either command reports success.

* Restore stacks after incomplete cascade rebases

Roll back branches already rewritten when a later rebase cannot start or
final ancestry verification fails, preventing retries from replaying stale
history. Preserve retryable modify state without repeating completed work,
and add regression coverage for remote-qualified trunk normalization.

* Avoid replaying amended parent commits

Preserve a branch's last valid base when its parent is rewritten, and only
use verified ancestor commits as rebase boundaries. Recover previously
corrupted metadata from the parent reflog when possible, otherwise stop
safely instead of replaying superseded parent commits.

* Record adopted branch merge bases

Store the actual common ancestor when adding an existing branch so cascade rebases replay only that branch's unique commits while retaining the amended-parent safety guard.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot-Session: 30bcbf2a-5ef1-4bdb-a0fc-618294ae8ded

---------

Copilot-Session: 30bcbf2a-5ef1-4bdb-a0fc-618294ae8ded

* clarify push behavior

* max stack size

* clarify only pushing active branches

* no stack obj in pull_request.opened event

* merge cmd

* Refine the merge TUI and simplify the async-merge client

Follow-up polish for `gh stack merge` (the command itself landed in the
previous commit). These changes refine the interactive wizard, enrich the
PR picker, and replace the merge client's bespoke HTTP handling with the
standard go-gh REST client.

Wizard and stepper:
- Redesign the top stepper as a segmented bar: completed steps are green,
  the active step is the brightest, and upcoming steps are dimmed. Steps
  are separated by a Powerline arrow that blends into the shading, with a
  graceful fallback to abutting segments on terminals that lack the glyph
  (e.g. Apple Terminal). Set GH_STACK_POWERLINE=1/0 to override detection.
- Show the stack number in the header ("Merge stack #123").
- Hide the header and stepper once the merge is submitted so the live
  progress view stands on its own.

PR picker:
- Render each pull request on two lines: the title (white/black, a touch
  bolder when selected) above its "#number • branch" (gray, fainter when
  deselected). Titles are fetched in one batched GraphQL query (PRTitles)
  and fall back to the branch name.
- Scroll long stacks in a fixed 10-item window with persistent "N more"
  indicators, so the list no longer jumps as those hints appear and
  disappear. Add shift+up / shift+down to jump to the top or bottom.

Progress and outcome:
- Always render a status line ("Submitting merge request...") so it does
  not pop in later and shift the view, and normalize messages to end in an
  ellipsis.
- Print the final result from the command layer rather than the TUI: a
  success line that includes the merge commit SHA
  ("Merged #1, #2 into main (abc1234)"), an atomic-rollback note on
  failure, a distinct message when the user stops watching an in-flight
  merge, and "Cancelled operation, nothing merged" on cancel.
- Clamp every rendered line to the terminal width so resizing no longer
  leaves duplicated header lines behind, and make truncation ANSI-aware.

Async-merge client:
- Use the go-gh REST client (c.rest.Put / c.rest.Get) for both the submit
  and poll endpoints, removing the bespoke http.Client, base-URL helper,
  and manual response decoding. The REST client discards non-2xx bodies,
  but that only costs the rare 400 message and 409 UUID: real merge
  failures still surface through the 200 poll body, and the in-range PRs
  are validated open, non-draft, and non-merged before submitting.
- Add classifyAsyncMergeError to map status codes to clear errors (404
  unavailable, 409 already exists, 400 no longer mergeable) and drop the
  now-unused AsyncMergeResult.StatusCode field. Rework the client tests to
  drive the REST client through a stub http.RoundTripper.

* warn merge queue unsupported

* update for new status field from api

* merge cmd docs

* more helpful error msgs

* update to support merge queue

* addressing review comments

* hide merge method step for merge queue

* set merge action explicitly

* address review comments to clarify docs on merge/api behavior

* async merge api docs

* address review comments

* Apply batched suggestions from code review

Co-authored-by: Tracy Lum <11878752+talum@users.noreply.github.com>
Co-authored-by: Sameen Karim <skarim@github.com>

---------

Co-authored-by: Tracy Lum <11878752+talum@users.noreply.github.com>

* break up skill into multiple files

* better reordering instructions

* updated branch placement instructions

* clarify branch naming

* recommend explicit arg for merge

* refine troubleshooting text

* address review comments

)

Bumps the npm_and_yarn group with 1 update in the /docs directory: [js-yaml](https://github.com/nodeca/js-yaml).


Updates `js-yaml` from 4.3.0 to 4.3.1
- [Changelog](https://github.com/nodeca/js-yaml/blob/4.3.1/CHANGELOG.md)
- [Commits](nodeca/js-yaml@4.3.0...4.3.1)

---
updated-dependencies:
- dependency-name: js-yaml
  dependency-version: 4.3.1
  dependency-type: indirect
  dependency-group: npm_and_yarn
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

* Add Vim navigation to stack view

* Advertise Vim navigation in stack modify

* Add Vim navigation to stack checkout

* Add Vim navigation to stack switch

* Advertise Vim navigation in stack merge

* detect remote stack from current branch

* clean up phrasing

* checkout by remote branch name

* address review comments

* offer to initialize stack when running add from outside a stack

* fetch trunk if missing locally

* disambiguate local trunk branch during init