Release v0.2.7

Changes from 0.2.6 to 0.2.7

What's Changed

• fix: keep SDK default system prompt empty by @sarahwooders in #194
• chore: declare packageManager and engines in package.json by @cpacker in #197
• Support restricted external dream workers by @sarahwooders in #188
• chore(deps): bump @letta-ai/letta-code from 0.27.30 to 0.28.17 by @dependabot[bot] in #199

Full Changelog: v0.2.6...v0.2.7