docs: add CLAUDE.md for development guidance

CLAUDE.md

@@ -0,0 +1,124 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Commands
+
+### Build and Development
+
+```bash
+# Initial setup (installs deps, builds, and configures)
+yarn setup
+
+# Start local development environment
+yarn start
+
+# Stop local environment
+yarn stop
+
+# Restart services
+yarn restart
+
+# Rebuild after changes
+yarn build
+
+# Complete reset of data and builds
+yarn reset
+```
+
+### Testing
+
+```bash
+# Run full test suite (requires running node from yarn start)
+yarn test
+
+# Test specific packages
+yarn test:suite              # Platform test suite
+yarn test:dapi               # DAPI components
+yarn test:sdk                # JavaScript SDK
+yarn test:dpp                # Dash Platform Protocol
+yarn test:drive              # Drive storage layer
+yarn test:wallet-lib         # Wallet library
+yarn test:dapi-client        # DAPI client
+
+# Test specific workspace
+yarn workspace <package_name> test
+```
+
+### Rust Development
+
+```bash
+# Run Rust tests for a specific package
+cargo test -p <package_name>
+
+# Run all Rust tests
+cargo test --workspace
+
+# Check Rust code
+cargo check --workspace
+
+# Run clippy linter
+cargo clippy --workspace
+
+# Format Rust code
+cargo fmt --all
+```
+
+### Other Commands
+
+```bash
+# Run linters
+yarn lint
+
+# Access dashmate CLI
+yarn dashmate
+
+# Configure test suite network
+yarn configure:tests:network
+```
+
+## Architecture
+
+### Technology Stack
+
+- **Rust**: Core platform components (Drive, DAPI server, DPP implementation)
+- **JavaScript/TypeScript**: Client SDKs, developer tools, test suite
+- **WebAssembly**: Bridge between Rust and JavaScript implementations
+- **gRPC**: Service communication protocol
+- **Docker**: Local development environment
+
+### Key Components
+
+**Drive** (`packages/rs-drive`): Platform's decentralized storage component, implementing a replicated state machine for storing and retrieving application data.
+
+**DAPI** (`packages/dapi`): Decentralized API server that provides a unified interface for interacting with the Dash network and Platform.
+
+**DPP** (`packages/rs-dpp`, `packages/wasm-dpp`): Dash Platform Protocol implementation that defines data structures and validation rules.
+
+**SDK** (`packages/js-dash-sdk`, `packages/rs-sdk`): Client libraries providing high-level interfaces for building applications on Dash Platform.
+
+**Dashmate** (`packages/dashmate`): Node management tool for setting up and managing Dash Platform nodes.
+
+### Data Contracts
+
+Platform uses data contracts to define application data schemas:
+- `dpns-contract`: Dash Platform Naming Service
+- `dashpay-contract`: Social payments functionality
+- `feature-flags-contract`: System feature toggles
+- `masternode-reward-shares-contract`: Masternode reward distribution
+- `withdrawals-contract`: Platform credit withdrawals
+
+### Development Workflow
+
+1. **Monorepo Structure**: Uses Yarn workspaces to manage multiple packages
+2. **Cross-language Integration**: WASM bindings connect Rust and JavaScript code
+3. **Local Development**: Docker Compose environment managed by dashmate
+4. **Testing**: Comprehensive test suites at unit, integration, and e2e levels
+
+### Important Patterns
+
+- **Platform Versioning**: Uses `rs-platform-version` for protocol versioning
+- **Serialization**: Custom serialization with `rs-platform-serialization`
+- **Value Handling**: `rs-platform-value` for cross-language data representation
+- **Proof Verification**: `rs-drive-proof-verifier` for cryptographic proofs
+- **State Transitions**: Documents and data contracts use state transitions for updates