v0.2 Phase 3: additive semantic tokens + KI-05 resolution

Additive token grammar (no renames, no replacements):

- --color-caution (dark #e8be4a, light #a08a1f) becomes the canonical
  name for tuned-amber notice surfaces in the new wrapper grammar
- --color-warning is kept as a CSS var() alias of --color-caution so
  every existing text-warning / bg-warning call site stays valid
- --color-info (dark #7a9ec0, light #3d6a8a) is the soft blue-grey
  signal for the new LumotiaNotice info variant
- --color-accent-environment (dark #8fae9a, light #4a7058) is an
  optional sage/moss support token for empty-state illustrations
  and environment-neutral status dots. NOT a brand swap — amber/
  copper --color-accent stays primary

Mirrored in src/design-system/colors_and_type.css (the buildless
preview pages bypass Tailwind so the duplication is intentional).

KI-05 resolved in the same commit, per the plan:

- src/lib/types/app.ts: drop `theme` from SettingsState
- src/lib/stores/page.svelte.ts: drop `theme: "Dark"` from defaults
- src/routes/+layout.svelte: drop the migration $effect, add a
  one-shot migrateLegacyTheme() on mount that copies any historical
  lumotia_settings.theme into preferences.theme and strips the
  legacy field. Idempotent — subsequent loads short-circuit
- src/routes/{float,viewer,preview}/+layout@.svelte: drop the same
  $effect; secondary windows inherit theme via PREFERENCES_CHANGED_EVENT
- src/lib/pages/SettingsPage.svelte: both SegmentedButton bindings
  (quick-settings row at :1272, Appearance group at :2606) now use
  Svelte 5 function bindings ({ get, set }) backed by prefs.theme
  and updatePreferences. No SegmentedButton API change

Phase 3 per-page gate green: npm run check (0/0/4129 files),
npm test (13/13), npm run test:e2e (16/16). No regressions in
the Phase 1 smoke baseline.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/release/v0.2-frontend-overhaul.md

@@ -199,8 +199,8 @@ Filled during execution. Each entry: phase #, date, what landed, what's next.
 |---|---|---|
 | 0 | ✅ complete | Doc written; tooling pins recorded |
 | 1 | ✅ complete | Tooling baseline green: `npm run check` clean, `npm test` clean, `npm run test:e2e` 16/16, `npm run guard:no-skeleton` clean, 10 screenshot artefacts. Browser-preview OS detection fixed (see Regression diary). |
-| 2 | pending | UI/form deps |
-| 3 | pending | Additive tokens + KI-05 |
+| 2 | ✅ complete | bits-ui 2.18.1, formsnap 2.0.1, sveltekit-superforms 2.30.1, zod 4.4.3, @internationalized/date 3.12.1. `npm audit signatures` 273 verified + 93 attestations. |
+| 3 | ✅ complete | New tokens `--color-caution`, `--color-info`, `--color-accent-environment` (dark + light), `--color-warning` aliased to `var(--color-caution)`. KI-05 resolved: `theme` dropped from SettingsState type + defaults, all four route-layout migration `$effect`s deleted, two SettingsPage SegmentedButton bindings repointed to `preferences.theme` via Svelte 5 function bindings, one-shot legacy-theme migration on first mount strips the field after copying. Gate green (check 0/0, vitest 13/13, e2e 16/16). |
 | 4 | pending | Wrapper alias layer |
 | 5 | pending | New primitives + design-system-v2 preview |
 | 6 | pending | Shell split |