AG-UI protocol gateway plugin for DeepSeek Harness

Key features

• Standard Cordis Service plugin exposed as ctx.agUi
• The current Agent-scoped browser Tool definitions join the ordinary DSH Tool schema list.
• The visible Tool schema list is sent on every model request and changes when the page advertises a different capability set.
• An unchanged Tool set preserves the Tool-schema prefix.
• Transport-neutral Agent-scoped browser Tool broker exposed as ctx.browserTools