Extends ticket 048's light_green pattern (light-inverted surface/border/text
scale + light's neutral danger colours, same base and accent hues as the
dark-surfaced counterpart) to the remaining five colour schemes across all
six files that must stay in sync: index.css, themes.ts, api.ts, settings.rs,
useSettingsPanel.ts, and NavMenu.tsx.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XFUNZwCvz3kcod3352ZR2o
