v0.4.0

Changelog

• 04f88c4 Merge pull request #3 from lunargate-ai/development
• 69f1aed feat(api): add typed local lifecycle
• e1a9693 feat(api): complete stored chat and compatibility hardening
• 2937440 feat(conversations): complete lifecycle ownership
• 20ce392 feat(gateway): establish lossless 0.4 API baseline
• 840943e feat(responses): proxy native lifecycle and streams
• 06c96e3 fix(api): close final compatibility review