feat(ui): map canvas follows light/dark theme; fix invisible gear control

The map view now selects a DARK_THEME or LIGHT_THEME palette from the
resolved app theme and threads it through every primitive builder, so
the canvas, planets, ship groups, cargo routes, battle/bombing markers,
fog, reach + selection rings, pending-Send tracks, and the pick overlay
all switch with the rest of the chrome. A theme flip remounts the
renderer preserving the camera — Pixi bakes the background at init and
every primitive bakes its colour at build, so a live re-tint is not
possible on the same instance.

This also fixes the reported bug: the gear-popover trigger and the
loading overlay hardcoded a dark navy background, so in light theme the
gear was invisible (dark icon on dark chip) until hover flipped it to a
white chip. Both now use the --color-surface-overlay token and read
correctly in both themes.

The light palette mirrors the dark one role-for-role, darkened /
saturated for contrast on a light background while keeping the incoming,
battle, and bombing accents vivid. The values are a first pass meant to
be refined during the F8 manual-QA loop.

Removes the now-dead "Phase 35" references from the code and lifts the
map-recoloring prohibition from the design-system / renderer docs; the
battle scene stays a fixed-palette data-viz surface.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ui/frontend/src/map/render.ts

@@ -226,12 +226,6 @@ const ORIGIN_COPY_INDEX = 4; // (0, 0) entry of TORUS_OFFSETS
 // debug surface stays allocation-free.
 const EMPTY_HIDDEN_IDS: ReadonlySet<PrimitiveID> = new Set();
 
-// FOG_COLOR is the Phase 29 visibility-fog colour. Two shades
-// lighter than the dark theme background (`0x0a0e1a`) so it reads
-// as a faint fog without contrasting against the rest of the map.
-// The colour is tunable in Phase 35 polish.
-export const FOG_COLOR = 0x12162a;
-
 /**
  * FogPaintOp is one item in the ordered draw sequence produced by
  * `fogPaintOps`. The renderer dispatches each op directly onto a
@@ -657,7 +651,7 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 		g.clear();
 		g.circle(spec.anchor.x, spec.anchor.y, spec.anchor.radius);
 		g.stroke({
-			color: PICK_OVERLAY_STYLE.anchor.color,
+			color: theme.pickHighlight,
 			alpha: PICK_OVERLAY_STYLE.anchor.alpha,
 			width: PICK_OVERLAY_STYLE.anchor.width,
 		});
@@ -665,7 +659,7 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 			g.moveTo(spec.line.x1, spec.line.y1);
 			g.lineTo(spec.line.x2, spec.line.y2);
 			g.stroke({
-				color: PICK_OVERLAY_STYLE.line.color,
+				color: theme.pickHighlight,
 				alpha: PICK_OVERLAY_STYLE.line.alpha,
 				width: PICK_OVERLAY_STYLE.line.width,
 			});
@@ -677,7 +671,7 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 				spec.hoverOutline.radius,
 			);
 			g.stroke({
-				color: PICK_OVERLAY_STYLE.hover.color,
+				color: theme.pickHighlight,
 				alpha: PICK_OVERLAY_STYLE.hover.alpha,
 				width: PICK_OVERLAY_STYLE.hover.width,
 			});
@@ -720,7 +714,7 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 				dimmedAlphaBackup.set(g, g.alpha);
 				dimmedTintBackup.set(g, g.tint as number);
 				g.alpha = PICK_OVERLAY_STYLE.dimAlpha;
-				g.tint = PICK_OVERLAY_STYLE.dimTint;
+				g.tint = theme.pickDimTint;
 			}
 		}
 		// Overlay graphic. Lives in the origin copy so the central
@@ -891,7 +885,7 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 			const ops = fogPaintOps(
 				opts.world,
 				circles,
-				FOG_COLOR,
+				theme.fog,
 				theme.background,
 				mode,
 			);