feat: add TownsPage and router configuration

- Created TownsPage.vue to display a list of towns with filtering options and a modal for details.
- Implemented a router.js file to manage application routes, including the new towns page.

src/pages/DocPage.vue

@@ -0,0 +1,19 @@
+<template>
+  <iframe
+    class="iframe-fullpage"
+    src="https://schema.lunadeer.cn/public/libraries/wco40gb6blucloqv"
+    frameborder="0"
+    allowfullscreen
+  ></iframe>
+</template>
+
+<style scoped>
+.iframe-fullpage {
+  position: fixed;
+  top: var(--bl-header-height);
+  left: 0;
+  width: 100%;
+  height: calc(100vh - var(--bl-header-height));
+  border: none;
+}
+</style>