feat(desktop): embed BoosAPI Desktop client as a subproject

Vendor the rebranded BoosAPI Desktop client (Tauri + Vue) into metapi as
a monorepo subdirectory under desktop/. Source only — node_modules,
dist, Cargo target and the upstream .git history are excluded.

desktop/ keeps its own independent Cargo workspace (desktop/src-tauri
with crates/*); it is not part of the backend boosapi crate, so a
`cargo check` at the metapi root still compiles only the backend. Build
the desktop app from desktop/src-tauri per desktop/README.md.

Note: app icons are still placeholder assets pending the final BoosAPI
logo. The updater signing keys live outside the repo and are not
included.

desktop/libs/stream-monaco/examples/streaming-demo/vite.config.ts

@@ -0,0 +1,19 @@
+import path from 'node:path'
+import vue from '@vitejs/plugin-vue'
+import { defineConfig } from 'vite'
+
+export default defineConfig({
+  plugins: [vue()],
+  resolve: {
+    alias: {
+      'stream-monaco': path.resolve(__dirname, '../../src'),
+    },
+  },
+  // Prevent Vite from pre-bundling the local package. If Vite optimizes it into
+  // node_modules/.vite/deps, relative worker URLs can be rewritten to that
+  // location and may become unreachable. Excluding the package keeps it as
+  // source so `new URL('./worker/..', import.meta.url)` resolves correctly.
+  optimizeDeps: {
+    exclude: ['stream-monaco'],
+  },
+})