Fix: Backspace with Select All active merges thoughts instead of deleting them

[Copilot]

When multiple thoughts are selected via Select All (cmd+opt+a) and the user presses Backspace, all thought text was merged into a single thought instead of the selected thoughts being deleted.

Root cause: deleteEmptyThoughtOrOutdent (bound to plain Backspace) called deleteEmptyThought unconditionally during multicursor execution. deleteEmptyThought merges a thought with its previous sibling — the wrong behavior when multiple thoughts are selected.

Changes

• src/commands/deleteEmptyThoughtOrOutdent.ts
  • In exec, check hasMulticursor(state) first and dispatch deleteThoughtWithCursor() instead of deleteEmptyThought when multiselect is active
  • Add clearMulticursor: true to the multicursor config so selection is cleared post-deletion
  • Add onComplete callback to show a "Deleted N thoughts." alert, consistent with the delete command

const exec: Command['exec'] = (dispatch, getState) => {
  const state = getState()
  if (hasMulticursor(state)) {
    dispatch(deleteThoughtWithCursor())  // delete instead of merge
  } else if (state.cursorCleared) {
    dispatch(deleteEmptyThought)
  } else if (canExecuteOutdent(state)) {
    dispatch(outdent())
  } else {
    dispatch(deleteEmptyThought)
  }
}

• src/e2e/puppeteer/__tests__/multiselect.ts
  • Add a Puppeteer test: paste 3 thoughts, select all, press Backspace, assert all thoughts are deleted

[raineorshine]

Th new puppeteer test is failing. Do not request a review until puppeteer tests pass.

[raineorshine]

This does not guarantee that the caret moves to the beginning of the thought, which is a requirement in the Steps to Reproduce.

[Copilot]

Fixed in commit 4a6a603. Now using click(editableC, { edge: 'left' }) followed by waitUntil(() => window.getSelection()?.focusOffset === 0) to explicitly place the caret at the beginning of 'C' before calling selectAll, matching the Steps to Reproduce.

[raineorshine]

Looks good, but the puppeteer test is failing.

[Copilot]

Looks good, but the puppeteer test is failing.

Fixed in commit 3e99feb. The root cause was that setCursor (called by the multicursor loop to set each cursor) clears state.multicursors, so hasMulticursor(state) always returned false inside exec. Changed to check state.isMulticursorExecuting instead, which is set to true by the multicursor execution loop before calling exec for each cursor.