feat(loldle): add ability and splash champion-guessing modules

Closes deferred phases 04 + 05 of loldle-new-modes plan.

- loldle-ability: 5 guesses, DDragon ability icon as photo. State pins
  slot (P/Q/W/E/R) so the same icon shows every turn. Abilities pulled
  from DDragon per-champion — same source loldle.net uses at runtime.
- loldle-splash: 4 guesses, random skin splash as photo. Skin pool
  scraped from loldle.net bundle (var Ad=[…] — 172 champs × 1939 skins,
  non-chroma, matches their splash mode exactly). URLs from Riot
  DDragon CDN (no version segment, stable across patches).
- fetch-ddragon-data.js: extended to write all four JSONs in one run.
  Shares a single DDragon per-champion fetch cycle (concurrency 10).
- Credits loldle.net + Riot Games in all loldle-family READMEs.

19 new tests (503 total). Lint clean. register:dry reports 12 loldle_*
commands with no conflicts.

src/modules/loldle-splash/index.js

@@ -0,0 +1,39 @@
+/**
+ * @file loldle-splash — guess the champion from splash art (random skin).
+ * Skin pool scraped from loldle.net, splash URLs from Data Dragon CDN.
+ */
+
+import { handleGiveup, handleSplash, handleStats } from "./handlers.js";
+
+/** @type {import("../../db/kv-store-interface.js").KVStore | null} */
+let db = null;
+
+/** @type {import("../registry.js").BotModule} */
+const loldleSplashModule = {
+  name: "loldle-splash",
+  init: async ({ db: store }) => {
+    db = store;
+  },
+  commands: [
+    {
+      name: "loldle_splash",
+      visibility: "public",
+      description: "Splash loldle — guess the champion from splash art",
+      handler: (ctx) => handleSplash(ctx, db),
+    },
+    {
+      name: "loldle_splash_giveup",
+      visibility: "public",
+      description: "Reveal the current splash loldle answer",
+      handler: (ctx) => handleGiveup(ctx, db),
+    },
+    {
+      name: "loldle_splash_stats",
+      visibility: "public",
+      description: "Show your splash loldle stats (wins, streak)",
+      handler: (ctx) => handleStats(ctx, db),
+    },
+  ],
+};
+
+export default loldleSplashModule;