ui/phase-16: cargo routes inspector + map pick foundation

Add per-planet cargo routes (COL/CAP/MAT/EMP) to the inspector with
a renderer-driven destination picker (faded out-of-reach planets,
cursor-line anchor, hover-highlight) and per-route arrows on the
map. The pick-mode primitives are exposed via `MapPickService` so
ship-group dispatch in Phase 19/20 can reuse the same surface.

Pass A — generic map foundation:
- hit-test now sizes the click zone to `pointRadiusPx + slopPx` so
  the visible disc is always part of the target.
- `RendererHandle` gains `onPointerMove`, `onHoverChange`,
  `setPickMode`, `getPickState`, `getPrimitiveAlpha`,
  `setExtraPrimitives`, `getPrimitives`. The click dispatcher is
  centralised: pick-mode swallows clicks atomically so the standard
  selection consumers do not race against teardown.
- `MapPickService` (`lib/map-pick.svelte.ts`) wraps the renderer
  contract in a promise-shaped `pick(...)`. The in-game shell
  layout owns the service so sidebar and bottom-sheet inspectors
  see the same instance.
- Debug-surface registry exposes `getMapPrimitives`,
  `getMapPickState`, `getMapCamera` to e2e specs without spawning a
  separate debug page after navigation.

Pass B — cargo-route feature:
- `CargoLoadType`, `setCargoRoute`, `removeCargoRoute` typed
  variants with `(source, loadType)` collapse rule on the order
  draft; round-trip through the FBS encoder/decoder.
- `GameReport` decodes `routes` and the local player's drive tech
  for the inline reach formula (40 × drive). `applyOrderOverlay`
  upserts/drops route entries for valid/submitting/applied
  commands.
- `lib/inspectors/planet/cargo-routes.svelte` renders the
  four-slot section. `Add` / `Edit` call `MapPickService.pick`,
  `Remove` emits `removeCargoRoute`.
- `map/cargo-routes.ts` builds shaft + arrowhead primitives per
  cargo type; the map view pushes them through
  `setExtraPrimitives` so the renderer never re-inits Pixi on
  route mutations (Pixi 8 doesn't support that on a reused
  canvas).

Docs:
- `docs/cargo-routes-ux.md` covers engine semantics + UI map.
- `docs/renderer.md` documents pick mode and the debug surface.
- `docs/calc-bridge.md` records the Phase 16 reach waiver.
- `PLAN.md` rewrites Phase 16 to reflect the foundation + feature
  split and the decisions baked in (map-driven picker, inline
  reach, optimistic overlay via `setExtraPrimitives`).

Tests:
- `tests/map-pick-mode.test.ts` — pure overlay-spec helper.
- `tests/map-cargo-routes.test.ts` — `buildCargoRouteLines`.
- `tests/inspector-planet-cargo-routes.test.ts` — slot rendering,
  picker invocation, collapse, cancel, remove.
- Extensions to `order-draft`, `submit`, `order-load`,
  `order-overlay`, `state-binding`, `inspector-planet`,
  `inspector-overlay`, `game-shell-sidebar`, `game-shell-header`.
- `tests/e2e/cargo-routes.spec.ts` — Playwright happy path: add
  COL, add CAP, remove COL, asserting both the inspector and the
  arrow count via `__galaxyDebug.getMapPrimitives()`.

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

ui/frontend/tests/order-draft.test.ts

@@ -328,6 +328,104 @@ describe("OrderDraftStore", () => {
 		store.dispose();
 	});
 
+	test("setCargoRoute collapses by (source, loadType) — newer wins", async () => {
+		const store = new OrderDraftStore();
+		await store.init({ cache, gameId: GAME_ID });
+		await store.add({
+			kind: "setCargoRoute",
+			id: "first",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 2,
+			loadType: "COL",
+		});
+		await store.add({
+			kind: "setCargoRoute",
+			id: "second",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 3,
+			loadType: "COL",
+		});
+		expect(store.commands.map((c) => c.id)).toEqual(["second"]);
+		expect(store.statuses["first"]).toBeUndefined();
+		expect(store.statuses["second"]).toBe("valid");
+		store.dispose();
+	});
+
+	test("setCargoRoute and removeCargoRoute share a collapse key", async () => {
+		const store = new OrderDraftStore();
+		await store.init({ cache, gameId: GAME_ID });
+		await store.add({
+			kind: "setCargoRoute",
+			id: "set",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 2,
+			loadType: "MAT",
+		});
+		await store.add({
+			kind: "removeCargoRoute",
+			id: "remove",
+			sourcePlanetNumber: 1,
+			loadType: "MAT",
+		});
+		expect(store.commands.map((c) => c.id)).toEqual(["remove"]);
+		// And remove → set on the same slot collapses again.
+		await store.add({
+			kind: "setCargoRoute",
+			id: "set2",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 4,
+			loadType: "MAT",
+		});
+		expect(store.commands.map((c) => c.id)).toEqual(["set2"]);
+		store.dispose();
+	});
+
+	test("cargo routes for different load-types or sources stay independent", async () => {
+		const store = new OrderDraftStore();
+		await store.init({ cache, gameId: GAME_ID });
+		await store.add({
+			kind: "setCargoRoute",
+			id: "p1-col",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 2,
+			loadType: "COL",
+		});
+		await store.add({
+			kind: "setCargoRoute",
+			id: "p1-cap",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 3,
+			loadType: "CAP",
+		});
+		await store.add({
+			kind: "setCargoRoute",
+			id: "p9-col",
+			sourcePlanetNumber: 9,
+			destinationPlanetNumber: 2,
+			loadType: "COL",
+		});
+		expect(store.commands.map((c) => c.id)).toEqual([
+			"p1-col",
+			"p1-cap",
+			"p9-col",
+		]);
+		store.dispose();
+	});
+
+	test("setCargoRoute is invalid when source equals destination", async () => {
+		const store = new OrderDraftStore();
+		await store.init({ cache, gameId: GAME_ID });
+		await store.add({
+			kind: "setCargoRoute",
+			id: "self",
+			sourcePlanetNumber: 1,
+			destinationPlanetNumber: 1,
+			loadType: "EMP",
+		});
+		expect(store.statuses["self"]).toBe("invalid");
+		store.dispose();
+	});
+
 	test("hydrateFromServer overwrites the local cache with the server snapshot", async () => {
 		const { fakeFetchClient } = await import("./helpers/fake-order-client");
 		const { client } = fakeFetchClient(GAME_ID, [