v0.1.19 — Production Hardening

Changes

Security & CI Hardening

• CI least-privilege: Added permissions: contents: read to CI workflow
• Coverage enforcement: Added --cov-fail-under=80 for protocol and core tests
• X402_MODE warning: load_config() now warns when X402_MODE is unset (prevents accidental test mode in production)
• Examples debug off: All TypeScript examples now default to debug: false

Dependency Safety

• Added version upper bounds to all Python dependencies (<1.0.0, <44.0.0 for cryptography)
• Prevents future breaking changes from silently breaking installs

Version Alignment

• All packages unified to v0.1.19 (core, protocol, adapters, npm)
• Fixed npm @ag402/fetch and @ag402/solana publish (previously stuck at 0.1.0)