docs: refresh architecture diagram and structure sections

docs/CONTRIBUTING.en.md

@@ -8,7 +8,7 @@ Thanks for your interest in contributing to DS2API!
 
 ### Prerequisites
 
-- Go 1.24+
+- Go 1.26+
 - Node.js 20+ (for WebUI development)
 - npm (bundled with Node.js)
 
@@ -94,6 +94,7 @@ Manually build WebUI to `static/admin/`:
 
 ```text
 ds2api/
+├── app/                    # Unified handler entry (shared by Vercel/local)
 ├── cmd/
 │   ├── ds2api/              # Local/container entrypoint
 │   └── ds2api-tests/        # End-to-end testsuite entrypoint

docs/CONTRIBUTING.md

@@ -8,7 +8,7 @@
 
 ### 前置要求
 
-- Go 1.24+
+- Go 1.26+
 - Node.js 20+（WebUI 开发时）
 - npm（随 Node.js 提供）
 
@@ -94,6 +94,7 @@ docker-compose -f docker-compose.dev.yml up
 
 ```text
 ds2api/
+├── app/                    # 统一 Handler 入口（供 Vercel / 本地共用）
 ├── cmd/
 │   ├── ds2api/              # 本地/容器启动入口
 │   └── ds2api-tests/        # 端到端测试集入口

docs/DEPLOY.en.md

@@ -24,7 +24,7 @@ This guide covers all deployment methods for the current Go-based codebase.
 
 | Dependency | Minimum Version | Notes |
 | --- | --- | --- |
-| Go | 1.24+ | Build backend |
+| Go | 1.26+ | Build backend |
 | Node.js | 20+ | Only needed to build WebUI locally |
 | npm | Bundled with Node.js | Install WebUI dependencies |
 
@@ -401,7 +401,7 @@ cp config.example.json config.json
 docker pull ghcr.io/cjackhwang/ds2api:latest
 
 # specific version (example)
-docker pull ghcr.io/cjackhwang/ds2api:v2.1.2
+docker pull ghcr.io/cjackhwang/ds2api:v3.0.0
 ```
 
 ---

docs/DEPLOY.md

@@ -24,7 +24,7 @@
 
 | 依赖 | 最低版本 | 说明 |
 | --- | --- | --- |
-| Go | 1.24+ | 编译后端 |
+| Go | 1.26+ | 编译后端 |
 | Node.js | 20+ | 仅在需要本地构建 WebUI 时 |
 | npm | 随 Node.js 提供 | 安装 WebUI 依赖 |
 
@@ -401,7 +401,7 @@ cp config.example.json config.json
 docker pull ghcr.io/cjackhwang/ds2api:latest
 
 # 指定版本（示例）
-docker pull ghcr.io/cjackhwang/ds2api:v2.1.2
+docker pull ghcr.io/cjackhwang/ds2api:v3.0.0
 ```
 
 ---