feat(frontend): add about page

frontend/vite.config.ts

@@ -1,8 +1,9 @@
 import { sveltekit } from "@sveltejs/kit/vite";
 import { defineConfig } from "vite";
+import { plugin as markdown, Mode as MarkdownMode } from "vite-plugin-markdown";
 
 export default defineConfig({
-  plugins: [sveltekit()],
+  plugins: [sveltekit(), markdown({ mode: [MarkdownMode.HTML] })],
   server: {
     proxy: {
       "/api": {