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/e2e/fixtures/order-fbs.ts

@@ -14,7 +14,10 @@ import {
 	CommandPayload,
 	CommandPlanetProduce,
 	CommandPlanetRename,
+	CommandPlanetRouteRemove,
+	CommandPlanetRouteSet,
 	PlanetProduction,
+	PlanetRouteLoadType,
 	UserGamesOrder,
 	UserGamesOrderGetResponse,
 	UserGamesOrderResponse,
@@ -48,9 +51,25 @@ export interface SetProductionTypeResultFixture
 	subject: string;
 }
 
+export interface SetCargoRouteResultFixture extends CommandResultFixtureBase {
+	kind: "setCargoRoute";
+	sourcePlanetNumber: number;
+	destinationPlanetNumber: number;
+	loadType: "COL" | "CAP" | "MAT" | "EMP";
+}
+
+export interface RemoveCargoRouteResultFixture
+	extends CommandResultFixtureBase {
+	kind: "removeCargoRoute";
+	sourcePlanetNumber: number;
+	loadType: "COL" | "CAP" | "MAT" | "EMP";
+}
+
 export type CommandResultFixture =
 	| PlanetRenameResultFixture
-	| SetProductionTypeResultFixture;
+	| SetProductionTypeResultFixture
+	| SetCargoRouteResultFixture
+	| RemoveCargoRouteResultFixture;
 
 export function buildOrderResponsePayload(
 	gameId: string,
@@ -135,6 +154,25 @@ function encodeItem(builder: Builder, c: CommandResultFixture): number {
 			payloadType = CommandPayload.CommandPlanetProduce;
 			break;
 		}
+		case "setCargoRoute": {
+			inner = CommandPlanetRouteSet.createCommandPlanetRouteSet(
+				builder,
+				BigInt(c.sourcePlanetNumber),
+				BigInt(c.destinationPlanetNumber),
+				cargoLoadTypeToFBS(c.loadType),
+			);
+			payloadType = CommandPayload.CommandPlanetRouteSet;
+			break;
+		}
+		case "removeCargoRoute": {
+			inner = CommandPlanetRouteRemove.createCommandPlanetRouteRemove(
+				builder,
+				BigInt(c.sourcePlanetNumber),
+				cargoLoadTypeToFBS(c.loadType),
+			);
+			payloadType = CommandPayload.CommandPlanetRouteRemove;
+			break;
+		}
 	}
 	CommandItem.startCommandItem(builder);
 	CommandItem.addCmdId(builder, cmdIdOffset);
@@ -169,3 +207,18 @@ function productionTypeToFBS(
 			return PlanetProduction.SHIP;
 	}
 }
+
+function cargoLoadTypeToFBS(
+	value: SetCargoRouteResultFixture["loadType"],
+): PlanetRouteLoadType {
+	switch (value) {
+		case "COL":
+			return PlanetRouteLoadType.COL;
+		case "CAP":
+			return PlanetRouteLoadType.CAP;
+		case "MAT":
+			return PlanetRouteLoadType.MAT;
+		case "EMP":
+			return PlanetRouteLoadType.EMP;
+	}
+}