Fix the toast journey failing with "Cannot fast-forward to the past" - #616

## Why

#542 replaces the app's interface with the one in the
[prototype](https://github.com/jameskoster/wordpress-contributor-toolkit-prototype),
drawn with the WordPress Design System. It was built in slices on
`redesign/wpds`, so that trunk, which releases are cut from, never held
a half-redesigned window. The window is whole now: the shell, the page
header and details, every card and dialog, and the tray. This pull
request is how the branch reaches trunk.

It lands before the last three sub-issues, on purpose. The settings
dialog (#559) and dark mode (#560) add to a finished window and do not
need a branch to hide in, and the guide (#561) is easier to rewrite
against what is on trunk. They follow as pull requests against trunk.

## What changes

Everything `redesign/wpds` holds; this pull request adds nothing of its
own. Each slice was reviewed in its own pull request against that
branch, and says there how to test it and what it leaves out.

- **The shell** (#555): a sites list, the page area and a footer, in a
larger window. #590
- **The page header and the details** (#556): the site's menu in the
header, and what the checkout is in a sidebar that can be put away.
#594
- **The site's page** (#557): the server and the build watch in the
header and the details
(#595); the ticket
card, the apply card with a preview dialog, and the list of a site's
tickets (#596,
#597,
#599); the
create-site, rename and delete dialogs
(#600,
#601);
confirmations as notices in the window's corner
(#602); the page's
notices, update card and setup checklist
(#605); the
terminal, logs, mail and the review dialogs painted with the design
system's tokens
(#606,
#608); and lint
rules that keep it so
(#609,
#610).
- **The tray** (#558): along the bottom of the window, holding the
terminal, the logs or the mail, with a count of unseen debug.log lines
on the footer
(#612,
#613,
#614,
#615).
- Along the way:
#611 (the site
menu's update item says why it is held), and three that tidy up before
landing: #616 (a
journey's race with the page's clock),
#617 (comments the
finished redesign made untrue) and
#618 (the server's
button by its present name in `AGENTS.md`).

**What a contributor will notice first:** the terminal, the logs and the
mail are no longer on the page but behind three buttons at the foot of
the window; the terminal is dark text on light; the server and the build
watch are started from the header; a patch is previewed in a dialog
before it is applied; and what worked is said in the window's corner.

**Not in this pull request:**

- The settings dialog (#559). Until it, nothing about how the window is
arranged is remembered across restarts: the details, the tray's height,
the apply card's fold.
- Dark mode (#560). The terminal reads its colours once, when it is
made, and will need to follow the theme.
- The user guide and its screenshots (#561), which describe the old
interface. They are published from release tags, so they are not wrong
until a release ships this; #561 is next, ahead of #559 and #560, for
that reason.
- How a mail is drawn, and how the window handles a link. Both are
unchanged and tracked separately.

## How to test this

Platforms: macOS and Windows, both. Buildkite builds signed artifacts
for this pull request; use the build for its current head, and check
that it is: a push to the branch makes earlier builds stale.

The suite, from the repository root, after `npm ci`:

```
npm run lint
npm test
npm run test:e2e
```

113 journeys walk every slice on macOS and Windows on each push. What
they do not do is run a real site: a clone of `wordpress-develop`, an
install, a build and a server are stood in for. The one test that does,
`real-setup.yml`, is run by hand and was run on this branch at `548c020`
(https://github.com/WordPress/contributor-toolkit/actions/runs/37298667056):
a Core site on macOS and on Windows and a Gutenberg site on macOS were
created, installed, built and served, and passed. **The Gutenberg site
on Windows did not finish.** Its first attempt was cancelled after 74
minutes inside the journey, a minute short of the limit that would have
failed it with evidence, so it says nothing about where it was; a second
attempt was still running when this was written and its result is not in
this description. The commits since `548c020` change a journey, comments
and prose.

**A pass by hand, on a real machine** (any platform; Apple Silicon for
the server, which no test on a pull request starts for real). It follows
the order a contributor meets things in:

1. Open the app with no sites. **Create new site**, a Core site, in a
folder with a space in its path. The setup checklist runs its steps; the
terminal's button at the foot of the window shows what each is doing.
2. Let the checklist's last step start the server, and finish
WordPress's own setup in the browser. Back in the app the header says
"Server running" and "Build watching". Stop the server and start it
again: from **Server running** in the header, or with **Stop** and
**Start** beside "Server" in the details.
3. Press the three buttons at the left of the footer in turn. Terminal:
type `help`. Logs: the server's lines, the build watch's, and Debug.log.
Email: where SMTP is listening. Drag the tray's top edge.
4. Link a ticket by its number. The card shows the ticket and its pull
requests and patches.
5. Apply one of them. The preview dialog names the files; **Apply and
rebuild** runs the steps on the card.
6. Edit a file under `src/`, then **Review & submit changes**. The diff
is the edit and nothing else.
7. Create a second site, or open one from before, and move between the
two from the sites list. Each has its own terminal, logs and mail.
8. **Update to latest trunk** from the site's menu.

**What must not have happened:** work lost in a link, an apply, a switch
or an update that did not say so; `node_modules` rebuilt where nothing
changed; a failure said only in a tray that stayed closed; one site's
output in another's tray; anything on the page under the tray.

**What cannot be tested by hand, and what was not:** none of the slices'
manual steps were run by a person. I looked at screenshots and drove the
app through the journeys; everything local was on macOS, with Windows
left to CI. This pass is the first one by hand.

## Risks and limitations

- **It is one commit on trunk**, since the repository allows only squash
merges. The slices' pull requests are its record. `redesign/wpds` should
not be branched from after this: it will have diverged from trunk.
- **Reviewed in slices, not as a whole.** Twenty-two pull requests, all
but a two-word change to `AGENTS.md` reviewed by a separate reviewer
context before they were opened, most in two passes; see below. The
branch was then swept once for what falls between slices, which found
comments and one unread field
(#617) and the
three points that follow.
- **Three questions and two failures still use the system's own
dialogs**: the discards ask through its confirm box, and a path that
could not be copied and a server started before there is a build are
said in its alert. #557 meant to replace them and did so for deletions
only.
- **Some dialogs are repainted, not rebuilt.** The review dialog and its
destinations, the mail dialog and the question an update asks about
loose edits have the design system's colours and type on the old
component library's parts.
- **A real Gutenberg setup on Windows is not shown to pass on this
branch.** See "How to test this". It passed on trunk before the
redesign, in 35 minutes; here it was past 46 on its second attempt.
Whether that is the runner or the branch is not known.
- **The guide describes the old interface** until #561. Do not cut a
release before it.
- **The bundle roughly doubled**
(#590): the sites
list brings `DataViews` and what it needs. Launch time was not measured.
- **Less is always in view.** A build's output, a new line in debug.log
and a caught mail are in a tray that may be closed. A failure opens the
terminal, or the logs if nothing else is open; unseen debug.log lines
are counted on the footer; a mail that arrives shows nowhere until its
tray is opened, which was decided and is not an oversight.
- **Translation is about half done.** The shell, the cards, the tray and
most dialogs go through the translator. Roughly 200 strings in
components and hooks do not yet (the review dialog and its destinations,
the setup checklist, the logs, most of what the hooks say), nor about
150 in the modules they take sentences from. Strings that are new are in
English in the shipped translations until they are translated.
- **Focus is lost in a few places**: when the app swaps what the tray
holds from under it, when a notice with a focused button goes, when a
row's own action removes the row.
- **Some failures are still worded by the main process** ("Error
invoking remote method…"): a failed rename, a failed setup.
- **Things carried over, not made by this:** a start that throws leaves
the server's button dead until a restart; erasing typed input in the
terminal breaks once the line wraps; a line written to debug.log while
it is being attached to can be shown twice.
- **#571 and
#603 will conflict
with trunk after this**, in the mail's journey and helpers and in the
dev server's hook.
- Each slice's own list has more, and says which of its limits were
chosen.

## Related

Closes #557. Closes #558. Part of #542, which stays open for #559, #560
and #561. #555 and #556 are closed already.

---

<details>
<summary>Design decisions and alternatives considered</summary>

- **An integration branch, and one landing.** A window drawn half by the
old view and half by the new one could not be released, and the slices
were too many to hold back one by one behind a flag. Fixes and changes
with no visible effect went to trunk first and were merged across, so
this diff is the redesign and little else.
- **Landing before #559 to #561.** The plan was to land when all seven
sub-issues were in the branch. The remaining three do not change what is
there: two add to it and one documents it. Holding a finished window on
a branch for them only lengthens the time trunk and the branch can drift
apart.
- **What the prototype lacks is kept and redrawn**, and what it has
somewhere else moves to where it puts it. Its labels are adopted. Where
a slice departs from it, the slice says so.

</details>

<details>
<summary>Review outcome (required — see AGENTS.md)</summary>

**No review of the whole diff was run. The record is the slices':
twenty-two pull requests into `redesign/wpds`, each but one reviewed
before it was opened by a separate, read-only reviewer context following
`.github/instructions/code-review.instructions.md`, most in two passes
(the change, then its fix-up), with the counts and the findings in each
pull request's own review outcome. The one is
#618, two words in
a line of prose.**

- **Review:** completed, per slice —
#590,
#594 to
#602,
#605,
#606,
#608 to
#617 (no review was
run for #618);
everything marked to fix in a slice was fixed in that slice, and what
was left is in its Risks.
- **Review:** completed, for leftovers only — a separate agent context,
read-only; `redesign/wpds` at `548c020` against trunk; not a review of
correctness, which the slices had: a search for dead CSS and code,
comments that waited for a slice that has landed, what is left of the
old component library and of the system's dialogs, strings not yet
translatable, and repository docs that name the branch. Nothing found in
the stylesheet, the dependencies or the docs; thirteen comments and one
unread field, fixed in
#617; the rest is
in Risks above.
- **CodeRabbit:** not run. Its check reads "Review skipped: automatic
reviews are disabled" on this pull request and on the slices, so the
slices' pre-PR reviews are the reviews of record, each for the head it
names.
- **Since review:** nothing was added to the branch outside a reviewed
slice, apart from three merges of trunk (`da19ac6`, `3344172`,
`23d46e7`).

</details>

<details>
<summary>Implementation notes</summary>

- `git diff origin/trunk...origin/redesign/wpds`: 148 files, about
14,800 lines added and 3,000 removed; about 6,300 of the added lines are
tests.
- The site's view, which was one component of five thousand lines, is
spread over the four regions the layout has: the header, the cards, the
details and the tray. Decisions are in `src/renderer/*.cjs` with unit
tests; components draw them.
- New for the suite: journeys per region under `tests/e2e/journeys/`,
lint rules of the repository's own (`eslint-rules/`), and Stylelint over
the window's stylesheet.
- The main process changed in one place for the redesign's sake: the
debug.log tail says which lines the file already held
(#614).

</details>

<details>
<summary>Screenshots or recording</summary>

Not attached: I have no way to upload images from the command line. The
prototype shows the design; the signed build shows the app.

</details>

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>