fix: do not cache POST requests using serviceWorker

Author: FRSgit

packages/index/src/serviceWorker.ts

@@ -9,7 +9,8 @@ const PAGES_TO_CONTROL = ['/', '/index.html'];
 
 const CACHE_NAME = 'frsource-cache-' + version;
 
-const typedSelf = self as ServiceWorkerGlobalScope & typeof globalThis;
+const typedSelf = self as unknown as ServiceWorkerGlobalScope &
+    typeof globalThis;
 
 urlsToCache.unshift(
     'https://www.frsource.org/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js',
@@ -48,6 +49,7 @@ typedSelf.addEventListener('activate', (event) => {
 typedSelf.addEventListener('fetch', function (event) {
     event.respondWith(
         (async () => {
+            if (event.request.method !== 'GET') return fetch(event.request);
             if (!event.clientId) return fetch(event.request);
 
             const client = await typedSelf.clients.get(event.clientId);