Problem:
- Unable to "pin" a window to prevent closing without specifically
being targeted.
- :fclose closes hidden windows (even before visible windows).
Solution:
- Add 'winpinned' window-local option. When set, window is skipped by
:fclose and :only. Pin the ui2 cmdline window (which should always be
visible), so that it is not closed by :only/fclose.
- Skip over hidden (and pinned) windows with :fclose.
Co-authored-by: glepnir <glephunter@gmail.com>
Problem:
- Not obvious which _meta/ are generated and which should be edited
manually.
- The require guard (`error('Cannot require a meta file')`) is not
consistently present in all meta files.
Solution:
- Update headers.
- Add require() guard to all meta files.
- Rename generated meta files with `.gen.lua`.
