Add crown cosmetic type (#4618)

## What

Adds **crowns** as a new cosmetic category, wired end-to-end like
flags/skins, plus a Crowns tab in the lobby cosmetics modal (#4617).

Catalog shape in cosmetics.json:

```json
"crowns": {
  "gold_crown": {
    "name": "gold_crown",
    "url": "...",
    "affiliateCode": null,
    "product": null,
    "priceHard": 5,
    "artist": "...",
    "rarity": "common"
  }
}
```

## Changes

- **Core**: `CrownSchema` + optional `crowns` record in
`CosmeticsSchema`; `crownName` in `PlayerCosmeticRefs`; resolved `crown:
{ name, url }` in `PlayerCosmetics`
- **Server**: `isCrownAllowed` in the privilege checker — requires a
`crown:*` or `crown:<name>` flare, resolves the ref to the catalog URL
- **Client**: crown selection persisted under the `crown` localStorage
key (stale/unowned selections self-clear), `crownRelationship` +
resolve/refs wiring, `"crown"` purchase type, Crowns tab in the store,
and a Crowns tab in the cosmetics modal (owned crowns + Default tile;
selecting persists and keeps the modal open)
- **i18n**: `store.crowns`, `store.no_crowns`
- Tests for schema parsing, privilege checks, and cosmetic resolution

## Not in this PR

- In-game rendering of `player.cosmetics.crown` (name pass /
leaderboards / player panel)
- API-side support (`/shop/purchase` accepting `cosmeticType: "crown"`,
granting `crown:<name>` flares, serving `crowns` in cosmetics.json)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

tests/ResolveCosmetics.test.ts

@@ -294,6 +294,75 @@ describe("resolveCosmetics", () => {
     });
   });
 
+  describe("crowns", () => {
+    const crown = {
+      name: "gold_crown",
+      url: "http://localhost:8787/public/cosmetics/crown/gold",
+      affiliateCode: null,
+      product,
+      priceSoft: undefined,
+      priceHard: 5,
+      artist: "sadfas",
+      rarity: "common",
+    };
+
+    test("includes crowns with correct key", () => {
+      const cosmetics = makeCosmetics({
+        crowns: { gold_crown: crown as any },
+      });
+      const result = resolveCosmetics(cosmetics, false, null);
+      const crownItem = result.find((r) => r.key === "crown:gold_crown");
+      expect(crownItem).toBeDefined();
+      expect(crownItem?.cosmetic).toEqual(crown);
+      expect(crownItem?.colorPalette).toBeNull();
+    });
+
+    test("purchasable when user has no flares and priceHard exists", () => {
+      const cosmetics = makeCosmetics({
+        crowns: { gold_crown: crown as any },
+      });
+      const result = resolveCosmetics(cosmetics, makeUserMe(), null);
+      const crownItem = result.find((r) => r.key === "crown:gold_crown");
+      expect(crownItem?.relationship).toBe("purchasable");
+    });
+
+    test("owned with wildcard flare", () => {
+      const cosmetics = makeCosmetics({
+        crowns: { gold_crown: crown as any },
+      });
+      const result = resolveCosmetics(cosmetics, makeUserMe(["crown:*"]), null);
+      const crownItem = result.find((r) => r.key === "crown:gold_crown");
+      expect(crownItem?.relationship).toBe("owned");
+    });
+
+    test("owned with specific flare", () => {
+      const cosmetics = makeCosmetics({
+        crowns: { gold_crown: crown as any },
+      });
+      const result = resolveCosmetics(
+        cosmetics,
+        makeUserMe(["crown:gold_crown"]),
+        null,
+      );
+      const crownItem = result.find((r) => r.key === "crown:gold_crown");
+      expect(crownItem?.relationship).toBe("owned");
+    });
+
+    test("blocked with no product and no price", () => {
+      const freeCrown = {
+        ...crown,
+        product: null,
+        priceHard: undefined,
+      };
+      const cosmetics = makeCosmetics({
+        crowns: { gold_crown: freeCrown as any },
+      });
+      const result = resolveCosmetics(cosmetics, makeUserMe(), null);
+      const crownItem = result.find((r) => r.key === "crown:gold_crown");
+      expect(crownItem?.relationship).toBe("blocked");
+    });
+  });
+
   describe("groupCosmeticVariants", () => {
     const patternVariant = (
       patternName: string,