panel.focusMode.exit is bound to Escape in the contributions layer, which
outranks the active preset. In Vim insert/visual mode that shadowed the
vim preset's `escape → vim.mode.normal` binding, so Esc closed the editor
instead of returning to normal mode.
Add an optional when-clause to a CommandContribution's defaultBinding
(plumbed through to KeymapService.registerCommandBinding, which already
accepts one) and guard focusMode.exit's escape with
`!vim.insert && !vim.visual` — symmetric with vim.yaml's vim.mode.normal.
Esc still exits focus / closes the editor in normal and non-Vim modes.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>