Extract Vue frontend into separate container and add stp_wasm crate

Move Vue app from nginx/vue/ to top-level vue/ with its own Dockerfile,
update docker-compose configs and nginx proxy to serve from the new
container, and add initial Rust WASM crate (stp_wasm). Also fix .gitignore
to exclude Rust target/ directories.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vue/src/views/admin/CreatePost.vue

@@ -0,0 +1,36 @@
+<script setup>
+import Button from "@/components/input/Button.vue";
+import { ref } from "vue";
+import { gql } from "@/graphql";
+
+const title = ref("");
+const content = ref("");
+
+async function post() {
+    try {
+        const data = await gql(
+            `mutation CreatePost($input: CreatePostInput!) { createPost(input: $input) { id } }`,
+            { input: { title: title.value, content: content.value } },
+        );
+        title.value = "";
+        content.value = "";
+        console.log(data.createPost);
+    } catch (err) {
+        console.error(err);
+    }
+}
+</script>
+
+<template>
+    <div class="flex flex-col">
+        <h1>Create Post</h1>
+        <input type="text" v-model="title" placeholder="Title" @keyup.enter="post" />
+        <textarea
+            class="h-50"
+            v-model="content"
+            placeholder="Content"
+        ></textarea>
+        <Button @click="post">Upload</Button>
+        <!-- make textarea take up most the space -->
+    </div>
+</template>