Release v0.20.0

What's Changed

• feat: add ping for sse server by @lcgash in #80
• fix(client): allow interface to be implemented by @jkoelker in #135
• feat: Tool Handler Middleware by @wimspaargaren in #123

New Contributors

• @lcgash made their first contribution in #80
• @jkoelker made their first contribution in #135
• @wimspaargaren made their first contribution in #123

Full Changelog: v0.19.0...v0.20.0