The CJK text options were behind per-language "Enable layout" toggles in
the file menu and the settings, each with its own sidebar section. A text
now has one language, picked in a single Language panel, and the options
of that language show below it.
- Rename the `vertical-text-layout` flag and feature to `cjk-support`.
- Remove the per-file and per-profile layout toggles, the file options
that stored them and the `:set-text-layout` change.
- Add the Language panel: a grouped dropdown of Japanese, Korean and the
regional Chinese variants, a row to change the language and a button to
remove it, "Mixed" when the selected texts differ. Picking a language
writes it to every paragraph of the texts.
- Render the CJK attrs only under the language that uses them, so a text
without language is horizontal and plain. The stored content keeps
every attr.
- Remember the last picked language for the next new texts.
- Add File > Language: the language of the texts without one of their
own, applied at render time and laid out again when it changes.
- Add the profile text language in Settings > Options: new files start
with it as their file language.
- Extract the grouped dropdown of the board size presets into a shared
component used by the presets and the Language panel.
- Name the Japanese readings furigana, drop the redundant prefixes of
the furigana and pinyin options, move Distribute below the writing
mode row and show only the position sides of the writing mode.
AI-assisted-by: claude-opus-5-5