v1.13.0 — LSP Multi-Language + Tests + Clean Config

Highlights

• LSP multi-language — Default support for Python (pyright), Rust (rust-analyzer), Go (gopls) + TypeScript/JavaScript
• Configurable LSP servers — Add custom LSP servers via lspServers in .coding-agent.json
• Full test coverage — 181 unit tests for MCP, LSP, persistence, toolRegistry, models
• Better MCP error messages — stderr captured in close errors
• Clean defaults — Empty mcpServers/lspServers in .coding-agent.json to avoid startup failures

Changes

• src/lsp/config.ts: LSP server config loader
• DEFAULT_LSP_SERVERS extended with pyright, rust-analyzer, gopls
• loadLSPConfig wired into agent.ts and server.ts startup
• StdioTransport: stderr captured and included in close errors
• 5 new test files (mcp, lsp, persistence, toolRegistry, models)
• transport.ts: fixed pending response resolution in readline handler
• Fixed config loaders: findProjectRoot returns dir path, not file path

Test suite

• 181 unit tests (previously 138)
• 12 test files covering all modules