chore: remove unused prettier dep and dead code

Drop prettier (no config, script, or eslint integration), the unused render-semaphore state() method and CreateRenderSemaphore typedef, and ignore .claude/settings.local.json.

renderer/src/lib/render-semaphore.js

@@ -20,12 +20,5 @@ export const createRenderSemaphore = (max) => {
     release() {
       active = Math.max(0, active - 1);
     },
-
-    /**
-     * @returns {{active: number, max: number}}
-     */
-    state() {
-      return {active, max};
-    },
   };
 };

renderer/src/routes/gif.js

@@ -5,7 +5,6 @@ import {parseWheelRequest} from '../schemas/wheel-request.js';
 
 /**
  * @typedef {import('../config.js').AppConfig} AppConfig
- * @typedef {import('../lib/render-semaphore.js').createRenderSemaphore} CreateRenderSemaphore
  * @typedef {import('../schemas/wheel-request.js').WheelRenderRequest} WheelRenderRequest
  */