feat(ui): F8-12 — map polish (zoom invariance, labels, selection, soft radius) (#55)

* Honest pixel-space sizing for `pointRadiusPx` / `strokeWidthPx`: the
  renderer divides by the current camera scale on every
  `viewport.zoomed` so thin lines / small markers stay the same on-screen
  size at any zoom.
* Known-size planets switch to `pointRadiusWorld`, softened against the
  reference scale by `PLANET_SIZE_ZOOM_ALPHA = 0.33`; unidentified
  planets pin to a 3-px disc.
* New planet label layer renders a two-line `name / #N` legend under
  each planet (`#N` only for unidentified or when the new `planetNames`
  toggle is off). Selection now paints an inverse-fill frame around the
  selected planet's label plus an outline on the disc; the old
  selection-ring primitive is retired.
* Bombing markers swap the separate CirclePrim for a planet-outline
  overlay (damaged / wiped colour); the report deep-link moves to a
  "view bombing report" link in the planet inspector.
* Docs + tests follow: `renderer.md` reflects the new sizing contract +
  label / outline layers, vitest covers the sizing math, label
  formatting, and the new toggle, and the map-toggles e2e adds a
  persistence case for `planetNames`.

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

ui/frontend/tests/e2e/map-toggles.spec.ts

@@ -365,9 +365,39 @@ test("toggle state persists across a page reload", async ({ page }) => {
 	expect(
 		await page.getByTestId("map-toggles-bombing-markers").isChecked(),
 	).toBe(false);
-	// Battle X-cross and bombing ring are hidden in the renderer.
+	// Battle X-cross primitives stay hidden in the renderer. F8-12 / #30
+	// retired the bombing CirclePrim — the toggle now hides a planet
+	// outline overlay, which sits outside the primitive surface; the
+	// high-bit 0xc… range is permanently empty.
 	expect(await visibleHighBitCount(page, 0xa0000000)).toBe(0);
-	expect(await visibleHighBitCount(page, 0xc0000000)).toBe(0);
+});
+
+test("planet-names toggle persists across a page reload (F8-12 / #29)", async ({
+	page,
+}) => {
+	await mockGateway(page, { currentTurn: 1 });
+	await bootSession(page);
+	await openGame(page);
+
+	await page.getByTestId("map-toggles-trigger").click();
+	// Default ON; flip it OFF.
+	expect(await page.getByTestId("map-toggles-planet-names").isChecked()).toBe(
+		true,
+	);
+	await page.getByTestId("map-toggles-planet-names").click();
+	expect(await page.getByTestId("map-toggles-planet-names").isChecked()).toBe(
+		false,
+	);
+
+	await page.reload({ waitUntil: "commit" });
+	await expect(page.getByTestId("active-view-map")).toHaveAttribute(
+		"data-status",
+		"ready",
+	);
+	await page.getByTestId("map-toggles-trigger").click();
+	expect(await page.getByTestId("map-toggles-planet-names").isChecked()).toBe(
+		false,
+	);
 });
 
 // settledRenderCount waits out the mount/resize paint burst and returns