feat: externalize buttplug as separate nginx container

- Add Dockerfile.buttplug: builds Rust/WASM + TS, serves via nginx
- Add nginx.buttplug.conf: serves /dist and /wasm with correct MIME types
- Add .gitea/workflows/docker-build-buttplug.yml: path-filtered CI workflow
- Strip Rust toolchain and buttplug build from frontend Dockerfile
- Move buttplug to devDependencies (types only at build time)
- Remove vite-plugin-wasm from frontend (WASM now served by nginx)
- Add /buttplug proxy in vite.config (dev: localhost:8080)
- Add buttplug service to compose.yml
- Load buttplug dynamically in play page via runtime import
- Fix faq page: suppress no-unnecessary-state-wrap for reassigned SvelteSet

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

packages/frontend/vite.config.ts

@@ -2,13 +2,17 @@ import path from "path";
 import tailwindcss from "@tailwindcss/vite";
 import { defineConfig } from "vite";
 import { sveltekit } from "@sveltejs/kit/vite";
-import wasm from "vite-plugin-wasm";
 
 export default defineConfig({
-  plugins: [sveltekit(), tailwindcss(), wasm()],
+  plugins: [sveltekit(), tailwindcss()],
   resolve: {
     alias: { $lib: path.resolve("./src/lib"), "@": path.resolve("./src/lib") },
   },
+  build: {
+    rollupOptions: {
+      external: ["@sexy.pivoine.art/buttplug"],
+    },
+  },
   server: {
     port: 3000,
     proxy: {
@@ -19,6 +23,11 @@ export default defineConfig({
         secure: false,
         ws: true,
       },
+      "/buttplug": {
+        rewrite: (path) => path.replace(/^\/buttplug/, ""),
+        target: "http://localhost:8080",
+        changeOrigin: true,
+      },
     },
   },
 });