feat(editor-shell): confirm before deleting a file from the tree

[demtario]

What

Deleting a file from the sidebar tree now asks first.

Why

The trash control sat 8px from Rename on a 24px row that only reveals its actions on hover, and fired onDeleteFile straight through. There is no undo — the file leaves the workspace immediately — so a mis-click was unrecoverable from inside the app.

How

FileTree holds pendingDelete next to its existing adding/renaming state and puts up the Dialog primitive from the same package, so Sidebar's onDeleteFile plumbing is untouched.

Deliberately unlike the demo-delete confirm in MyDemos: no busy state, no disabled buttons, no in-flight guard on onClose. That one revokes a share link over the network; this one is a synchronous in-memory splice of the workspace, and nothing persists until save or fork. The copy says that rather than borrowing "this can't be undone".

Three details that are load-bearing rather than cosmetic:

• The confirm button is named "Delete file", not "Delete". A row's trash control is already named "Delete" by its title, and Playwright matches accessible names by substring — two identically-named buttons make every unscoped locator ambiguous while the dialog is open.
• Cancel carries data-autofocus. Without it focus lands on the first content control, which is the destructive one, and Space or Enter would carry out the delete the dialog exists to ask about (see Dialog's own note on the hatch).
• The buttons outline with controlBorder, not border. Dark's border is #222222, the same value as the surfaceRaised dialog card, so that outline would have no visible edge — the same trap as d1cfb17 on the top bar.

Two staleness guards: the dialog renders outside the !collapsed branch so collapsing the section cannot strand an open modal, and pendingDelete is cleared when its path leaves paths. A path that left and came back — example switched away and back, or the same name re-added — would otherwise re-open the dialog unprompted, asking about a delete nobody started.

Testing

Full deterministic e2e suite passes (52 tests, 0 failures; baseline on the branch point is 51/0). packages/editor-shell typechecks clean.

• sidebar-crud.spec.ts and editor-tabs.spec.ts route their existing delete click-throughs via the dialog, and each asserts the row survives the click that only asks.
• New case in sidebar-crud.spec.ts: Cancel is focused on open, Space on it is harmless, Escape also dismisses, and the file survives both.

Verified separately that the overlay escapes the 240px sidebar track it is nested inside, since toBeVisible() would pass on a card clipped into that column just as well. A throwaway probe measured it at 0,0 1280×720 against a 1280×720 viewport, with the 360px card centred at x=460 and elementFromPoint landing inside it. No portal needed; the probe is not part of the diff.

Notes

apps/authoring typecheck reports two pre-existing errors on DemoRuntime.reload (App.tsx:1277,1280). Confirmed present on the branch point, untouched here.

MyDemos.tsx:775 has the same invisible-outline bug on its Cancel button (border on a surfaceRaised card). Left alone to keep this diff to the ask — worth a one-token follow-up.

🤖 Generated with Claude Code

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Note

Low Risk
UI-only guard around existing synchronous delete; no auth, persistence, or API changes.

Overview
Sidebar file delete is no longer immediate: trash opens a Delete this file? dialog, and onDeleteFile runs only after Delete file. Copy clarifies the change is in-memory until save/fork.

FileTree tracks pendingDelete, clears it when the path leaves the workspace or the section collapses (dialog renders outside the collapsed branch), and uses Cancel with data-autofocus so keyboard focus does not land on the destructive control. The confirm button is labelled Delete file to avoid clashing with row trash Delete in tests and accessibility.

E2E flows confirm through the dialog; a new test covers Cancel focus, Space, and Escape without deleting.

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