add CLAUDE.md

Author: chadparker

CLAUDE.md

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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+GitHub Copilot for Xcode is a macOS application that provides AI-powered code completion and chat assistance for Xcode. It integrates GitHub Copilot's capabilities directly into the Xcode development environment through Xcode source editor extensions.
+
+## Build Commands
+
+### Local Development Build
+```bash
+cd ./Script
+sh ./uninstall-app.sh    # Remove any previous installation
+del ../build             # Clean the build directory (use del instead of rm)
+sh ./localbuild-app.sh   # Build a fresh copy of the app
+```
+
+### Server Components (Node.js/TypeScript)
+```bash
+cd Server
+npm install              # Install dependencies
+npm run build           # Build with webpack
+```
+
+### Testing
+```bash
+# Run all unit tests (from Xcode or command line)
+xcodebuild test -scheme "Copilot for Xcode" -workspace "Copilot for Xcode.xcworkspace"
+
+# Tests are configured in TestPlan.xctestplan
+# All new tests should be added to this test plan
+```
+
+### Code Formatting
+- Uses SwiftFormat for Swift code formatting
+- Follows Ray Wenderlich Style Guide with 4 spaces for indentation
+
+## Architecture Overview
+
+The project is organized into several key targets and packages:
+
+### Main Targets
+- **Copilot for Xcode**: Host app containing XPCService and editor extension, provides settings UI
+- **EditorExtension**: Xcode source editor extension that forwards editor content to XPCService
+- **ExtensionService**: Background service where all core features are implemented
+- **CommunicationBridge**: Maintains communication between host app/editor extension and ExtensionService
+
+### Swift Packages
+- **Core**: Contains main application logic organized by feature areas
+  - `Service`: ExtensionService implementation
+  - `HostApp`: Host application implementation
+  - `SuggestionWidget`: UI components for code suggestions
+  - `ConversationTab`: Chat interface components
+  - `ChatService`: Chat functionality and context management
+  - `SuggestionService`: Code completion service
+  - `PromptToCodeService`: Code generation from prompts
+
+- **Tool**: Shared utilities and lower-level services
+  - `GitHubCopilotService`: Core integration with GitHub Copilot Language Server
+  - `Workspace`: File system and project management
+  - `XcodeInspector`: Xcode app monitoring and interaction
+  - `SuggestionBasic`: Core suggestion data types
+  - `Preferences`: Configuration management
+  - `Logger`: Logging infrastructure
+
+- **Server**: Node.js/TypeScript components
+  - Monaco editor integration for diff views
+  - Terminal/xterm integration
+  - Webpack-based build system
+
+### Key Service Architecture
+- Uses actor-based concurrency with `@WorkspaceActor` and `@ServiceActor`
+- Dependency injection via swift-dependencies
+- Composable Architecture (TCA) for UI state management
+- XPC communication between sandboxed and non-sandboxed components
+
+### Data Flow
+1. Editor extension captures Xcode content via source editor APIs
+2. Content forwarded to ExtensionService via CommunicationBridge XPC
+3. ExtensionService processes requests through GitHubCopilotService 
+4. Language Server Protocol (LSP) communication with GitHub Copilot backend
+5. Results returned through same XPC chain back to editor
+
+## Prerequisites
+
+- macOS 12+
+- Xcode 8+
+- Node.js and npm (symlinked to /usr/local/bin for Xcode run scripts)
+- GitHub Copilot subscription
+
+## Key Files to Understand
+
+- `Core/Sources/Service/Service.swift`: Main service entry point
+- `Tool/Sources/GitHubCopilotService/LanguageServer/GitHubCopilotService.swift`: Core Copilot integration
+- `Core/Package.swift` & `Tool/Package.swift`: Swift package configurations
+- `TestPlan.xctestplan`: Centralized test configuration
+- `Version.xcconfig`: Version control for all targets
+- `DEVELOPMENT.md`: Detailed development setup and architecture notes
+
+## Common Development Patterns
+
+- All async operations use Swift concurrency (async/await)
+- UI built with SwiftUI using Composable Architecture patterns  
+- Preference storage via UserDefaults with type-safe property wrappers
+- Logging via centralized Logger package with different log levels
+- File watching and workspace management through dedicated services
+- XPC communication follows request-response patterns with proper error handling