Code highlighting reused brand tokens (accent/text/border/muted), so it couldn't
be themed independently. Add syntax_string/number/keyword/comment skin keys →
syntax* theme tokens (defaulting to those brand tokens, so defaults are
unchanged) and point the highlighter at them. Documented in the element→key map.
Theming was semantic-only: the gold tool `●` was `accent`, shared with
headings/links/chevrons, so "recolor tool calls" was impossible and the agent
had no key to point at. Add `ui_tool` (● + tool spinner) and `ui_thinking`
(reasoning body) tokens that fall back to accent/muted — defaults unchanged,
but now independently settable. Make diffs skinnable too (`diff_*`), which
fromSkin previously hardcoded. Document the full element→key map in the skill so
Hermes knows which knob turns what.
Make the Python skin engine the single source of truth for a canonical theme
shape consumed by every surface, so a skin authored in $HERMES_HOME/skins/*.yaml
(by a user or by Hermes from a prompt) themes the CLI, TUI, and desktop GUI at
once — the theme analogue of the plugin SDK.
- @hermes/shared: canonical `HermesSkin` token shape + `SKIN_COLOR_TOKENS` enum,
consumed by both TS surfaces (TUI `GatewaySkin` and desktop dedup onto it).
- Desktop: `skinToDesktopTheme` resolver (skin → CSS-var palette, VS Code-style
derive-from-seed) + `backend-sync` that registers backend skins into the theme
registry (Appearance/Cmd-K/`/skin`) and applies on a real change. Seeds on
gateway.ready (never stomps a persisted pick), applies on skin.changed and the
post-turn `config.get skin` poll (catch-all for agent-edited config.yaml).
- TUI: `fromSkin` now maps the status bar + `background` keys it was dropping.
- Gateway: `config.get skin` also returns the full resolved palette (additive).
- Skill: `hermes-themes` teaches the agent to author + activate a skin.
Each surface keeps its own normalizing resolver (ansi for the TUI, CSS vars for
the desktop, prompt_toolkit/Rich for the CLI).
