fix(ui-map): move fog overlay to a viewport-level layer below the copies

Two regressions surfaced once visible-hyperspace toggled on a real
dev-deploy map:

1. On the zero-turn map the bg holes painted ON TOP of the planet
   glyphs — every LOCAL planet looked like a hollow circle of
   background colour instead of the planet pixel inside an
   unfogged area.
2. On a legacy report with a drive tech that pushes the visibility
   radius well past the world dimensions the bg circles overlapped
   to cover the entire viewport. Combined with the wrong z-order
   the result was a uniformly black canvas with every primitive
   hidden.

The per-copy implementation added the fog container via
`copy.addChildAt(container, 0)` and trusted Pixi v8 to insert the
container at the start of the copy's children. Whether by a Pixi
quirk or by some interaction with how `populatePrimitives` orders
its `c.addChild(g)` calls, the fog ended up rendering after every
primitive in practice — the symptoms above are a perfect match for
that ordering.

Restructured the fog rendering so the z-order is structural
rather than relying on `addChildAt`:

- A single `fogLayer: Container` is added to the viewport BEFORE
  the nine torus copies. Pixi renders viewport children in order,
  so the layer is guaranteed to paint first; every copy renders
  on top.
- `fogPaintOps` now emits world-space coordinates with wrap
  offsets baked in (9 fog rects + 9 bg circles per visibility
  entry in torus mode, 1 + N in no-wrap mode). The renderer
  populates `fogLayer` with one `Graphics` per op — no per-copy
  iteration on the fog side.
- The previous `fogGraphics: Container[]` closure state is gone.
  Each `setVisibilityFog` flip drops every child of `fogLayer`
  and rebuilds it. The dispose path drops the children
  eagerly before `app.destroy({children: true})` walks the tree.

The fog-paint-ops test exercises the new contract: the no-wrap
path keeps one rect + N circles, the torus path expands to nine
rects + nine wrapped circles per entry (including the seam-fix
case at x = 950).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/frontend/src/map/render.ts

@@ -243,29 +243,26 @@ export type FogPaintOp =
 
 /**
  * fogPaintOps returns the ordered sequence of paint operations that
- * draw the Phase 29 visible-hyperspace overlay on a single torus
- * copy. The first op is the fog-coloured rectangle covering the
- * full world; subsequent ops are background-coloured circles, one
- * per visibility circle, painted on top of the fog rectangle. The
- * natural rendering order unions overlapping circles for free —
- * earlier iterations relied on Pixi v8's `Graphics.cut()` to
- * subtract holes, but `cut()` produced incorrect unions for
- * overlapping circles (the symptom was a handful of disconnected
- * arc segments instead of a clean union).
+ * draw the Phase 29 visible-hyperspace overlay. The renderer
+ * dispatches each op onto its own Pixi `Graphics` inside a single
+ * `fogLayer` that sits below every primitive copy, so the natural
+ * rendering order paints fog underneath the world.
+ *
+ * Coordinates are in world space (the `fogLayer` has no transform),
+ * which means the wrap offsets are baked directly into the
+ * positions — there is no per-tile dispatch on the renderer side.
  *
  * `mode` controls the torus-wrap behaviour:
  *
- *   - `"torus"`: every visibility circle is also drawn at the eight
- *     wrapped positions (±width, ±height) so the circle remains
- *     visually continuous when its painted area extends past the
- *     world rectangle into a neighbouring tile — without the wraps
- *     the next tile's fog rectangle overpaints the bleed, producing
- *     a "sector" artifact at the seam.
- *   - `"no-wrap"`: only the planet's own position is drawn. The
- *     wrapped positions would create extra holes inside the world
- *     rectangle when a planet sits near an edge (the user can never
- *     pan past the boundary in no-wrap mode, but the wrapped circle
- *     could still leak into the visible area).
+ *   - `"torus"`: every fog rect AND every visibility circle is
+ *     emitted at the nine offsets (`(dx, dy) ∈ {-1, 0, 1}²`), so
+ *     the fog covers all nine torus tiles and a planet near a seam
+ *     keeps a continuous visibility hole across it.
+ *   - `"no-wrap"`: only the central tile is emitted. The user can
+ *     never pan past the boundary in no-wrap mode, so the
+ *     additional wraps would just be wasted paint — worse, a
+ *     wrapped circle from a planet near an edge would leak into
+ *     the visible world rectangle as an unwanted hole.
  *
  * Empty `circles` returns an empty list — the caller skips fog
  * rendering entirely. Width/height ≤ 0 also returns empty so a
@@ -282,17 +279,18 @@ export function fogPaintOps(
 	if (world.width <= 0 || world.height <= 0) return [];
 	const offsets: ReadonlyArray<readonly [number, number]> =
 		mode === "torus" ? TORUS_OFFSETS : ORIGIN_ONLY_OFFSET;
-	const ops: FogPaintOp[] = [
-		{
+	const ops: FogPaintOp[] = [];
+	for (const [dx, dy] of offsets) {
+		ops.push({
 			kind: "fillRect",
-			x: 0,
-			y: 0,
+			x: dx * world.width,
+			y: dy * world.height,
 			width: world.width,
 			height: world.height,
 			color: fogColor,
 			alpha: 1,
-		},
-	];
+		});
+	}
 	for (const c of circles) {
 		for (const [dx, dy] of offsets) {
 			ops.push({
@@ -343,6 +341,17 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 
 	app.stage.addChild(viewport);
 
+	// Phase 29 fog layer: a single Container sharing the viewport's
+	// coordinate space, populated by `setVisibilityFog`. Added to
+	// the viewport BEFORE the nine torus copies so the layered
+	// repaint (fog rectangles + background-coloured circles) always
+	// renders underneath every primitive. An earlier per-copy
+	// approach with `copy.addChildAt(fog, 0)` ended up with fog on
+	// top in practice — moving the fog to a sibling of the copies
+	// avoids any reorder ambiguity.
+	const fogLayer = new Container();
+	viewport.addChild(fogLayer);
+
 	// Create nine torus copies, each holding its own primitive
 	// graphics. Origin copy is always visible; the other eight
 	// follow the active wrap mode.
@@ -368,17 +377,10 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 	// renderer-internal hit-test sites (pointer-move, clicked) and the
 	// external `handle.hitAt` thread it through `hitTest`.
 	let hiddenIds: ReadonlySet<PrimitiveID> = EMPTY_HIDDEN_IDS;
-	// Per-copy fog Containers for the Phase 29 visibility fog
-	// overlay. Each container holds one `Graphics` per
-	// `FogPaintOp` (fog rect + one bg-coloured circle per
-	// visibility circle × wrap position), inserted at index 0 of
-	// the torus copy so primitives paint on top. Created lazily
-	// when `setVisibilityFog` first receives a non-empty list and
-	// destroyed wholesale on every subsequent call — Pixi v8's
-	// multi-shape Graphics is supported in theory, but stacking
-	// each fill on its own Graphics removes any risk of an
-	// internal-state regression dropping a layer.
-	let fogGraphics: Container[] = [];
+	// `fogLayer` (declared above) is repopulated every time
+	// `setVisibilityFog` runs. We track the dispatched ops only
+	// implicitly via the layer's children; on every flip we drop
+	// the previous children and rebuild from the new op list.
 	const applyHiddenStateTo = (id: PrimitiveID, list: Graphics[]): void => {
 		const visible = !hiddenIds.has(id);
 		for (const g of list) g.visible = visible;
@@ -804,16 +806,13 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 		},
 		isPrimitiveHidden: (id) => hiddenIds.has(id),
 		setVisibilityFog: (circles) => {
-			// Drop the old fog Containers first — every flip rebuilds
-			// from scratch instead of mutating in place, so the
-			// implementation stays simple and Pixi-v8-residue-free.
-			// `destroy({children: true})` propagates to every owned
-			// Graphics inside the Container.
-			for (const c of fogGraphics) {
-				c.parent?.removeChild(c);
-				c.destroy({ children: true });
+			// Drop the previous fog children — every flip rebuilds
+			// from scratch instead of mutating in place. Pixi v8's
+			// `Container.removeChildren()` returns the detached
+			// children so we can destroy each one explicitly.
+			for (const old of fogLayer.removeChildren()) {
+				old.destroy({ children: true });
 			}
-			fogGraphics = [];
 			const ops = fogPaintOps(
 				opts.world,
 				circles,
@@ -822,29 +821,21 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 				mode,
 			);
 			if (ops.length === 0) return;
-			for (const copy of copies) {
-				const container = new Container();
-				// One Graphics per op — the fog rect first, then every
-				// background-coloured circle on top. Per-shape Graphics
-				// removes any risk of multi-shape Pixi quirks dropping a
-				// layer (the previous all-in-one Graphics implementation
-				// surfaced exactly that symptom in DEV — only the last
-				// planet's glyph stayed visible inside the bg holes).
-				for (const op of ops) {
-					const g = new Graphics();
-					if (op.kind === "fillRect") {
-						g.rect(op.x, op.y, op.width, op.height);
-					} else {
-						g.circle(op.x, op.y, op.radius);
-					}
-					g.fill({ color: op.color, alpha: op.alpha });
-					container.addChild(g);
+			// Each op gets its own Graphics so any multi-shape Pixi
+			// quirks cannot drop a layer (an earlier all-in-one
+			// implementation surfaced exactly that symptom in DEV —
+			// only the last planet's glyph stayed visible inside the
+			// bg holes). The ops carry world-space positions; the
+			// `fogLayer` has no transform.
+			for (const op of ops) {
+				const g = new Graphics();
+				if (op.kind === "fillRect") {
+					g.rect(op.x, op.y, op.width, op.height);
+				} else {
+					g.circle(op.x, op.y, op.radius);
 				}
-				// Fog sits below every primitive on the same copy so
-				// planet glyphs paint on top. `addChildAt(g, 0)` keeps
-				// the rest of the children's order intact.
-				copy.addChildAt(container, 0);
-				fogGraphics.push(container);
+				g.fill({ color: op.color, alpha: op.alpha });
+				fogLayer.addChild(g);
 			}
 		},
 		resize: (w, h) => {
@@ -869,15 +860,15 @@ export async function createRenderer(opts: RendererOptions): Promise<RendererHan
 				teardownPickMode();
 				previous?.onPick(null);
 			}
-			// `app.destroy({...children: true})` below would also walk
-			// fog containers, but we drop them eagerly so the closure
-			// reference clears even if a future caller queries the
-			// renderer mid-dispose.
-			for (const c of fogGraphics) {
-				c.parent?.removeChild(c);
-				c.destroy({ children: true });
+			// `app.destroy({...children: true})` below recursively
+			// destroys every container in the scene graph, fogLayer
+			// included. The explicit removeChildren()/destroy here
+			// drops the fog children eagerly so a future caller
+			// querying the renderer mid-dispose does not see stale
+			// fog instances still parented under the layer.
+			for (const old of fogLayer.removeChildren()) {
+				old.destroy({ children: true });
 			}
-			fogGraphics = [];
 			viewport.off("moved", enforceCentreWhenLarger);
 			viewport.off("moved", wrapTorusCamera);
 			viewport.off("clicked", handleViewportClicked);