ui/phase-16: pick any planet in reach + stronger pick-mode dim

The cargo-route picker filtered out unidentified planets, so an
early-game player who had spotted but not surveyed a destination
could not configure a route to it — the engine has no such
restriction (`game/internal/controller/route.go.PlanetRouteSet`
only checks ownership of the origin and `util.ShortDistance(...) <=
FligthDistance`). Drop the unidentified guard and document the
contract in `cargo-routes-ux.md` plus a comment over `reachableSet()`.

Pick-mode dim now drops both alpha and tint on out-of-reach
planets so bright shapes (`STYLE_LOCAL` is `0x6dd2ff`) collapse
into a single muted gray. The single-channel `dimAlpha=0.3` was too
gentle against the dark theme — the user reported the dim wasn't
visible. Tighten to `dimAlpha=0.35 + dimTint=0x303841`; restore
both on tear-down.

Also threads through the user's `pkg/calc/race.go.FligthDistance`
addition: `calc-bridge.md` records the new Go-side reference (the
engine's `Race.FlightDistance()` already wraps it), and the picker
comment points at the canonical formula location.

Tests:
- `inspector-planet-cargo-routes.test.ts` adds two cases — a
  reach-spans-every-kind case (own + foreign + uninhabited +
  unidentified all picked when in range) and a successful pick to
  an unidentified destination.
- All 356 vitest cases + chromium-desktop / webkit-desktop e2e
  cargo-routes pass.

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

ui/frontend/src/lib/inspectors/planet/cargo-routes.svelte

@@ -104,11 +104,18 @@ The component is purposely deferential to the existing infrastructure:
 	const reach = $derived(40 * localPlayerDrive);
 
 	function reachableSet(): Set<number> {
+		// The engine accepts a route from a player-owned planet to any
+		// planet inside the source's flight distance — own, foreign,
+		// uninhabited, and unidentified all qualify (`game/internal/
+		// controller/route.go.PlanetRouteSet` only checks ownership of
+		// the origin and `util.ShortDistance(...) <= FligthDistance`,
+		// see `pkg/calc/race.go`). The picker mirrors that contract;
+		// only the source itself is excluded so a self-route cannot be
+		// emitted.
 		const ids = new Set<number>();
 		if (reach <= 0) return ids;
 		for (const candidate of planets) {
 			if (candidate.number === planet.number) continue;
-			if (candidate.kind === "unidentified") continue;
 			const dx = torusShortestDelta(planet.x, candidate.x, mapWidth);
 			const dy = torusShortestDelta(planet.y, candidate.y, mapHeight);
 			if (Math.hypot(dx, dy) <= reach) {

ui/frontend/src/map/pick-mode.ts

@@ -151,10 +151,20 @@ export function computePickOverlay(
  * PICK_OVERLAY_STYLE captures the colours / widths the renderer
  * applies to each spec channel. Exported so tests and future themes
  * can read the same values.
+ *
+ * `dimAlpha` and `dimTint` are applied together to non-reachable
+ * primitives during a pick session: the alpha drops their
+ * brightness, and the tint multiplies their fill colour toward dark
+ * gray so the colour identity (planet kind) collapses into a
+ * single muted shade. The combination has to read as "obviously
+ * disabled" against the dark theme — bright planets such as
+ * `STYLE_LOCAL` (`0x6dd2ff`) survive a 0.3 alpha alone too
+ * comfortably, so the tint pulls them down too.
  */
 export const PICK_OVERLAY_STYLE = {
 	anchor: { color: 0xffe082, alpha: 0.9, width: 2 },
 	line: { color: 0xffe082, alpha: 0.5, width: 1 },
 	hover: { color: 0xffe082, alpha: 1, width: 2 },
-	dimAlpha: 0.3,
+	dimAlpha: 0.35,
+	dimTint: 0x303841,
 } as const;

ui/frontend/src/map/render.ts

@@ -380,6 +380,7 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 	let pickOptions: PickModeOptions | null = null;
 	let pickOverlay: Graphics | null = null;
 	const dimmedAlphaBackup = new Map<Graphics, number>();
+	const dimmedTintBackup = new Map<Graphics, number>();
 	const detachPickListeners: Array<() => void> = [];
 
 	const handleViewportClicked = (e: {
@@ -462,6 +463,8 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 		detachPickListeners.length = 0;
 		for (const [g, alpha] of dimmedAlphaBackup) g.alpha = alpha;
 		dimmedAlphaBackup.clear();
+		for (const [g, tint] of dimmedTintBackup) g.tint = tint;
+		dimmedTintBackup.clear();
 		if (pickOverlay !== null) {
 			pickOverlay.destroy();
 			pickOverlay = null;
@@ -484,7 +487,9 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 			if (options.reachableIds.has(id)) continue;
 			for (const g of list) {
 				dimmedAlphaBackup.set(g, g.alpha);
+				dimmedTintBackup.set(g, g.tint as number);
 				g.alpha = PICK_OVERLAY_STYLE.dimAlpha;
+				g.tint = PICK_OVERLAY_STYLE.dimTint;
 			}
 		}
 		// Overlay graphic. Lives in the origin copy so the central