[BOUNTY] Create TypeScript SDK Package Structure and Core Utilities

[TeapoyY]

Bounty: Create TypeScript SDK Package Structure and Core Utilities

Reward: Per bounty specification | Domain: SDK

Changes

Created the foundational TypeScript SDK package (@privacylayer/sdk) for PrivacyLayer with the following structure and implementations:

Package Structure

sdk/ ├── package.json # Package configuration with all dependencies ├── tsconfig.json # Strict TypeScript configuration ├── .eslintrc.js # ESLint with TypeScript support ├── .prettierrc # Code formatting rules ├── jest.config.js # Jest test configuration with coverage thresholds ├── README.md # Installation and usage documentation ├── src/ │ ├── index.ts # Main exports + PrivacyLayer client class │ ├── types.ts # Note, Denomination, DepositReceipt, NetworkConfig, etc. │ ├── constants.ts # NETWORKS config, MERKLE_TREE_DEPTH, FIELD_SIZE │ ├── utils/ │ │ ├── index.ts │ │ ├── crypto.ts # randomFieldElement, hashPair, computeCommitment, deriveNullifier │ │ ├── encoding.ts # bytesToHex, hexToBytes, hexToBase64, etc. │ │ └── validation.ts # validateAddress, validateAmount, validateFieldElement, etc. │ └── __tests__/ │ └── utils.test.ts # Comprehensive unit tests for all utilities └── dist/ # Build output (generated on npm run build)

Key Implementations

• Core Types: Note, Denomination enum, DepositReceipt, NetworkConfig, MerkleProof, ValidationResult
• Cryptographic Utils: Random field element generation, Pedersen-like hashing, commitment/nullifier derivation
• Encoding Utils: Hex/bytes/base64 conversion, bigint serialization
• Validation Utils: Stellar address validation, amount validation, field element validation, transaction hash validation
• PrivacyLayer Client: Basic client class with network configuration

Build & Test

pm run build compiles TypeScript to dist/ with type declarations

pm test runs Jest with all utility tests

pm run coverage validates >80% coverage threshold

pm run lint validates TypeScript with ESLint

Files Changed

• sdk/package.json - New package with dependencies
• sdk/tsconfig.json - TypeScript strict configuration
• sdk/.eslintrc.js - ESLint rules
• sdk/.prettierrc - Prettier formatting
• sdk/jest.config.js - Jest with 80% coverage threshold
• sdk/README.md - Documentation
• sdk/src/index.ts - Main SDK exports
• sdk/src/types.ts - Type definitions
• sdk/src/constants.ts - Constants and network configs
• sdk/src/utils/crypto.ts - Cryptographic utilities
• sdk/src/utils/encoding.ts - Encoding utilities
• sdk/src/utils/validation.ts - Validation utilities
• sdk/src/utils/index.ts - Utils barrel export
• sdk/src/tests/utils.test.ts - Unit tests

Acceptance Criteria

• Package structure created with all files
• [x]
  pm install ready (dependencies specified)
• [x]
  pm run build compiles TypeScript successfully
• [x]
  pm test runs Jest tests
• [x]
  pm run lint passes ESLint checks
• Type definitions exported correctly
• README with installation and basic usage
• All utility functions have unit tests
• Code coverage >80% (configured)

Closes #7