Add OpenHands link to agents overview (#296)

Author: ignatov

docs/overview/agents.mdx

@@ -17,5 +17,6 @@ The following agents can be used with an ACP Client:
 - [Kimi CLI](https://github.com/MoonshotAI/kimi-cli)
 - [LLMling-Agent](https://phil65.github.io/llmling-agent/advanced/acp_integration/)
 - [OpenCode](https://github.com/sst/opencode)
+- [OpenHands](https://docs.openhands.dev/openhands/usage/run-openhands/acp)
 - [Stakpak](https://github.com/stakpak/agent?tab=readme-ov-file#agent-client-protocol-acp)
 - [VT Code](https://github.com/vinhnx/vtcode/blob/main/README.md#zed-ide-integration-agent-client-protocol)