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/website/docs/ru/index.md

@@ -0,0 +1,57 @@
+---
+layout: home
+title: "BoosApi — open-source AI-десктоп клиент и gateway"
+titleTemplate: false
+
+head:
+  - - meta
+    - name: description
+      content: "BoosApi — бесплатный open-source AI desktop client с multi-model chat, Agent, MCP, импортом ChatGPT/Cherry Studio/Kelivo, local RAG, S3/WebDAV backup и встроенным AI gateway."
+
+hero:
+  name: BoosApi
+  text: "Ваш AI-десктоп workspace"
+  tagline: "Мультимодельный чат, Agent, MCP-инструменты, API gateway, импорт данных, база знаний и backups в одном local-first клиенте"
+  image:
+    src: /logo.png
+    alt: BoosApi
+  actions:
+    - theme: brand
+      text: "Начало работы"
+      link: /ru/guide/getting-started
+    - theme: alt
+      text: "Скачать"
+      link: /ru/download
+    - theme: alt
+      text: GitHub
+      link: https://github.com/BoosApi-Desktop/BoosApi
+
+features:
+  - icon: robot
+    title: "Мультимодельный чат"
+    details: "OpenAI, Claude, Gemini, DeepSeek, Qwen и compatible APIs с key rotation, branches, compression и multi-model answers."
+  - icon: api
+    title: "Быстрое подключение"
+    details: "boosapi:// links, CC Switch import, custom headers, proxy settings, OpenAI Responses и per-model extra_body."
+  - icon: thunderbolt
+    title: "AI Agent"
+    details: "File edits, commands и code analysis с permission levels, working-directory sandbox, approval UI и cost tracking."
+  - icon: edit
+    title: "Рендеринг контента"
+    details: "Markdown, LaTeX, Mermaid, D2, Monaco code blocks, HTML fragments и Artifact previews."
+  - icon: search
+    title: "Search & RAG"
+    details: "Web search с citations, query generation, local sqlite-vec knowledge bases, rerank settings и retrieval feedback."
+  - icon: cloud-server
+    title: "API Gateway"
+    details: "Локальные OpenAI-compatible, OpenAI Responses, Claude и Gemini endpoints для Claude Code, Codex, OpenCode и custom tools."
+  - icon: book
+    title: "Импорт данных"
+    details: "ChatGPT official exports, Cherry Studio backups и Kelivo backups с duplicate handling и optional provider migration."
+  - icon: lock
+    title: "Backup и безопасность"
+    details: "AES-256 local storage, dual-root data layout, local/WebDAV/S3 backups и restore workflows."
+  - icon: desktop
+    title: "Desktop experience"
+    details: "11 languages, tray mode, always-on-top, global shortcuts, auto-start, proxy support и auto-update checks."
+---