Put the app on the culpeo palette

[dfalling]

Summary

Moves the app off the blue/teal/purple/green scheme onto the same ten semantic roles the web app was rewritten onto (canvas, surface, ink, muted, line, accent, accentText, onAccent, danger, plus three alpha variants). One declaration per role, no isDark ? … : … at any use site.

The old palette had four accent hues carrying meaning that wording and icons already carried, and its neutrals were cool greys against what is now a warm canvas — effectively two palettes fighting.

What changed

Accent is spent only where the guide sanctions it — primary button, map pins, focus rings, selected states. Badges, chips, category labels and the avatar go neutral. The "Completed" tag traded green for a ✓.

Search results no longer distinguish by hue. The three result kinds had accent/purple/grey circles behind their glyphs — three colours ~1.1:1 apart in luminance, i.e. indistinguishable without colour vision. They share one neutral treatment now; the section headings already say which is which.

Colours that came from dependencies, not from us. None would turn up in a grep of this repo:

Surface	Was	Now
MapLibre location puck	#33B5E5 hardcoded in its layer paint	replaced via <UserLocation>'s children
Emoji picker	fixed light theme — opened as a white sheet in dark mode	its theme prop, mapped onto tokens
<Switch>	Material colorPrimary	solid muted on / line/30 off
Every <ActivityIndicator>	platform colorAccent	explicit
Caret, handles, ripple, pre-JS window	AppCompat defaults	styles.xml + new values-night/

Basemap liberty → positron — 44 declared colours at 0.178 mean saturation down to 29 at 0.026, for the same reason web moved to a dataviz style. The pins are the content; the map is context.

Navigator theme built from our tokens instead of React Navigation's, so the gap during a push transition is the canvas.

Two corrections to the shared palette

Both apply to web too, at the same ratios:

• Focus was invisible. Inputs used the same neutral border at rest and focused, so focusing a field produced no visible change — a WCAG 2.4.7 failure that looked fine in the code. New TextField moves the border to accent with a ring, and owns the placeholder/caret/selection colours.
• line was doing two jobs with two different bars. As a divider it can be as quiet as it likes; but it was also a text input's border, and surface is only 1.06:1 against canvas (1.10:1 dark), so the border is the whole affordance. In dark mode that measured 1.32:1 — a field you can't find at night. Split out lineControl (#7a6f69, one value for both schemes) for load-bearing boundaries. Dividers keep line and are unchanged.

Verification

tsc, biome check, 51 tests, and :app:processDebugResources all pass.

Every control boundary and text pairing clears WCAG AA in both schemes — worst case 3.29:1 against the 3:1 non-text bar, 4.04:1 → 13.24:1 for chip text after moving line/15 fills to ink (muted on line/15 fails AA in light).

Not yet driven on a device. A linter can't catch "focus produces no visible change," so the states that need eyes on them: a focused field, the Completed toggle, the emoji picker, the map at night, and a cold start for the window background.

Findings worth porting back to web are written up in addendum.md alongside the style guide.