- Add diagnosticsStore to capture Push model notifications
- Handle textDocument/publishDiagnostics notifications in processBuffer
- Fix workspace/configuration response for JSON LSP validation
- Add missing language mappings (json, html, css, sh, fish, md, tf)
- diagnostics() now tries Pull first, falls back to Push store
- Add LSPServerManager for connection pooling with idle cleanup
- Add lsp_prepare_rename and lsp_rename tools
- Add lsp_code_actions and lsp_code_action_resolve tools
- Add WorkspaceEdit types and applyWorkspaceEdit utility
- Improve LSP client robustness with stderr buffering and process state tracking
