* feat: configure sidebar min/max width via [ui]
Expose the previously hardcoded MIN_SIDEBAR_WIDTH / MAX_SIDEBAR_WIDTH
clamps as [ui] sidebar_min_width / sidebar_max_width. Defaults remain
18 / 36 so existing configs are unchanged. Hot-reload is wired through
the existing [ui] block; reload re-clamps the live width to the new
bounds so tightening takes effect immediately.
Reject inverted bounds (min > max) at every entry point so a bad config
can never reach u16::clamp(min, max), which panics: App::new falls back
to defaults, and apply_live_config treats the whole [ui] section as
invalid and returns a partial reload report.
refs #132
* test: keep sidebar reload width within bounds
refs #132
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Co-authored-by: Ogulcan Celik <ogulcancelik@gmail.com>
Ogulcan Celik
CHIH,GODLEE
Zack Drach