Switch out of an input method and back with a lone Shift (#14975)

* Switch out of an input method and back with a lone Shift

Fcitx's alternate trigger only acts while an engine like Pinyin is or was
active, so Shift + letter and plain Latin typing are unaffected. It needs
Shift releases intact, which the both-Shifts Caps Lock option prevented.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Follow XDG_CONFIG_HOME in the Shift migration and test it

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

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Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

manual/34-keyboard-mouse-trackpad.md

@@ -61,7 +61,7 @@ On Dell XPS laptops with a haptic touchpad, you can also set the click strength
 
 Select Japanese, Korean, Chinese (Simplified, Pinyin), or Chinese (Traditional, Zhuyin) when the installer asks for your keyboard. Omarchy configures the keyboard and matching input engine automatically, including during offline first-boot setup. Japanese uses Mozc, Korean uses standard two-set Hangul, Simplified Chinese uses Pinyin, and Traditional Chinese uses Chewing's standard Zhuyin arrangement. Japanese (US keyboard) provides Mozc with a US keyboard layout.
 
-Typing starts in Latin mode. Press `Super + I` to cycle through configured input methods, and `Super + Shift + I` to cycle back. On Japanese keyboards, 全角/半角 toggles input, 変換 turns it on, and 無変換 turns it off. On a Korean keyboard layout, dedicated 한/영 and 한자 keys switch Hangul and convert to Hanja. `Ctrl + Space` stays available for Tmux and Herdr; `Shift + CapsLock` stays the compose key.
+Typing starts in Latin mode. Press `Super + I` to cycle through configured input methods, and `Super + Shift + I` to cycle back. Tap `Shift` on its own to step out of an input method like Pinyin into Latin letters, and tap it again to go back, the way Sogou, Microsoft Pinyin, and macOS work; `Shift` plus a letter still types a capital. On Japanese keyboards, 全角/半角 toggles input, 変換 turns it on, and 無変換 turns it off. On a Korean keyboard layout, dedicated 한/영 and 한자 keys switch Hangul and convert to Hanja. `Ctrl + Space` stays available for Tmux and Herdr; `Shift + CapsLock` stays the compose key.
 
 The keyboard indicator appears on the right of the bar when you have multiple keyboard layouts or input methods. Click it to switch input languages; Japanese displays あ for hiragana. For Japanese character choices, switch to Japanese, type a word such as `nihongo`, then press Space twice. Press Enter to accept your choice. If you also have multiple keyboard layouts, right-click the indicator to cycle those.