Two small dev-mode UX changes.
1. Banner. When CFG_DEV_MODE is on, a 36px amber-tinted strip sits flush
under the topbar with "You are currently running in Developer mode"
and a dismiss X. Dismissal is remembered in localStorage and cleared
whenever dev mode is toggled back on, so re-enabling the mode brings
the banner back. Body picks up `.has-dev-banner` while visible to
bump padding-top by the strip's height (also adjusts the mobile
drawer's top/height).
2. Toast. The auto-enable message dropped the trailing
"Click the LibrePortal logo 10× to disable." — too noisy on every
git/local page load; the easter egg is still discoverable. New
message is just "Developer mode auto-enabled — you're on a <mode>
install."
Signed-off-by: librelad <librelad@digitalangels.vip>
5655835398