prices: fold groceries and CS skins into one price tracker (/trackers/prices) with tabs

- tab registry in #lib/price-trackers (add a tab = route + entry + icon)
- groceries -> /trackers/prices/groceries (owner-only), CS prices -> /trackers/prices/cs (public)
- old /trackers/groceries/* and /projects/cs-prices/* redirect (301 GET, 308 POST) with query
- nav: one prices entry replaces groceries and skins; cyan price-tag icon

src/lib/server/owner.test.ts

@@ -22,6 +22,10 @@ describe('owner gate', () => {
 		expect(isOwnerWritePath('/trackers/tasks')).toBe(true);
 		expect(isOwnerOnlyPath('/trackers/groceries')).toBe(true);
 		expect(isOwnerWritePath('/trackers/groceries')).toBe(true);
+		expect(isOwnerOnlyPath('/trackers/prices/groceries/stats')).toBe(true);
+		expect(isOwnerWritePath('/trackers/prices/groceries')).toBe(true);
+		expect(isOwnerOnlyPath('/trackers/prices/cs')).toBe(false);
+		expect(isOwnerWritePath('/trackers/prices/cs/api/series')).toBe(false);
 		expect(isOwnerOnlyPath('/trackers/data-holders')).toBe(true);
 		expect(isOwnerWritePath('/trackers/data-holders')).toBe(true);
 		expect(isOwnerOnlyPath('/trackers/houses')).toBe(true);