release(v0.2.0): streaming, MCP protocol, Browser Hand, security enhancements

## Major Features

### Streaming Response System
- Implement LlmDriver trait with `stream()` method returning async Stream
- Add SSE parsing for Anthropic and OpenAI API streaming
- Integrate Tauri event system for frontend streaming (`stream:chunk` events)
- Add StreamChunk types: Delta, ToolStart, ToolEnd, Complete, Error

### MCP Protocol Implementation
- Add MCP JSON-RPC 2.0 types (mcp_types.rs)
- Implement stdio-based MCP transport (mcp_transport.rs)
- Support tool discovery, execution, and resource operations

### Browser Hand Implementation
- Complete browser automation with Playwright-style actions
- Support Navigate, Click, Type, Scrape, Screenshot, Wait actions
- Add educational Hands: Whiteboard, Slideshow, Speech, Quiz

### Security Enhancements
- Implement command whitelist/blacklist for shell_exec tool
- Add SSRF protection with private IP blocking
- Create security.toml configuration file

## Test Improvements
- Fix test import paths (security-utils, setup)
- Fix vi.mock hoisting issues with vi.hoisted()
- Update test expectations for validateUrl and sanitizeFilename
- Add getUnsupportedLocalGatewayStatus mock

## Documentation Updates
- Update architecture documentation
- Improve configuration reference
- Add quick-start guide updates

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

config/config.toml

@@ -128,7 +128,11 @@ retry_delay = "1s"
 # ============================================================
 
 [llm.aliases]
-"glm-5" = "zhipu/glm-4-plus"
+# 智谱 GLM 模型 (使用正确的 API 模型 ID)
+"glm-4-flash" = "zhipu/glm-4-flash"
+"glm-4-plus" = "zhipu/glm-4-plus"
+"glm-4.5" = "zhipu/glm-4.5"
+# 其他模型
 "qwen3.5" = "qwen/qwen-plus"
 "gpt-4" = "openai/gpt-4o"