add radio

docs/PLAN.md

@@ -148,6 +148,14 @@ graph TD
 
 Omarchy `colors.toml` maps almost 1:1: `lighter_background` → `surface`, `dark_background`/`darker_background` → elevation depth, `dark_foreground` → muted foreground, `accent` → `primary`/`accent`/`ring`, `red` → `destructive`, `green`/`yellow`/`orange` → success/warning. Every mapping lives in one module; never literals. Tests assert finite, distinct, semantically sane tokens for every preset × mode.
 
+The set stays role-minimal and grows one concept at a time, driven by the unit that needs it. Known planned additions:
+
+- **Overlay scrim + shadow/elevation tokens** — with the overlay units (Popover/Dialog/Menu, unit 11+); §5.5's popup elevation promise. No current role covers the modality backdrop.
+- **`success` / `warning` roles** — with the first severity-bearing component (Toast, badges, validation); the Omarchy mapping above already anticipates them.
+- **`knob` / control-fill role** — only if Slider (unit 7) confirms the Switch's borrowed roles (`primary_foreground` thumb, `border` off-track) as a second consumer; until then no expansion.
+
+Controls through unit 10 paint from existing roles and ramps.
+
 ### 5.3 Platform matrix
 
 | Target | Detection | Sources read | Live changes |