Replace specific switches with switch numbers

[tshu-w]

Should we change specific switches with switch numbers? This may be convenient for people who have modified the switches.

rime-prelude/key_bindings.yaml

Lines 45 to 48 in dd84abe

	- { when: always, accept: Control+Shift+2, toggle: ascii_mode }
	- { when: always, accept: Control+Shift+3, toggle: full_shape }
	- { when: always, accept: Control+Shift+4, toggle: simplification }
	- { when: always, accept: Control+Shift+5, toggle: extended_charset }

    - { when: always, accept: Control+Shift+2, toggle: '@0' }
    - { when: always, accept: Control+Shift+3, toggle: '@1' }
    - { when: always, accept: Control+Shift+4, toggle: '@2' }
    - { when: always, accept: Control+Shift+5, toggle: '@3' }
    - { when: always, accept: Control+Shift+6, toggle: '@4' }