desloppify: code health overhaul plus abuse hardening (140 green, strict 87.2)

Honest baseline after removing 45 gaming suppressions. Structural: lib/game plus root hooks extraction, CORS origin echo, DEV_ORIGINS layering. Fixes: error-cause binding, discord 5xx split, null-cache guard, co-located tests, rejecting-fetch coverage, naming and typing cleanup, socket controller, cache bound, cascade helpers, latch resets. Hardening: per-IP rate limit on API routes, deterministic-miss UX, retry cooldown plus cap. Suite 140 green, build plus lint clean.

test/fixtures.ts

@@ -0,0 +1,66 @@
+import type { GiteaRepo } from "@/lib/gitea";
+import type { GameProfile } from "@/lib/game/game-profile-types";
+import type { LanyardData } from "@/lib/game/lanyard";
+
+export function profileFixture(overrides: Partial<GameProfile> = {}): GameProfile {
+    return {
+        applicationId: "1",
+        gameId: "1",
+        gameUrl: "https://discord.com/games/1",
+        name: "Test Game",
+        genres: ["RPG"],
+        description: "A test game",
+        developers: ["Dev"],
+        publishers: ["Pub"],
+        releaseDate: "2024-01-15",
+        platforms: ["Windows"],
+        links: [],
+        coverUrl: null,
+        artworkUrl: null,
+        screenshots: [],
+        steamId: "100",
+        steamUrl: "https://store.steampowered.com/app/100/",
+        igdbUrl: null,
+        steamReviews: null,
+        itad: null,
+        sources: { igdb: false, steam: true, itad: false },
+        ...overrides,
+    };
+}
+
+export function lanyardFixture(overrides: Partial<LanyardData> = {}): LanyardData {
+    return {
+        discord_user: {
+            id: "1",
+            username: "testuser",
+            global_name: "Test User",
+            display_name: "Test User",
+            discriminator: "0",
+            avatar: null,
+            bot: false,
+        },
+        activities: [],
+        discord_status: "online",
+        active_on_discord_desktop: true,
+        active_on_discord_mobile: false,
+        active_on_discord_web: false,
+        listening_to_spotify: false,
+        spotify: null,
+        ...overrides,
+    };
+}
+
+export function repoFixture(): GiteaRepo {
+    return {
+        id: 1,
+        name: "demo",
+        fullName: "fristy/demo",
+        description: "A demo repo",
+        language: "TypeScript",
+        htmlUrl: "https://git.fristy.net/fristy/demo",
+        website: null,
+        stars: 3,
+        forks: 1,
+        updatedAt: "2026-01-01T00:00:00Z",
+    };
+}