Clarify CopilotKit Runtime guidance for AG-UI

[samjulien]

Summary

• Clarifies CopilotKit Runtime as the server-side connection layer for production Agent Framework AG-UI apps.
• Adds Copilot Runtime to the AG-UI security guidance as a concrete trusted frontend server option.
• Fixes small copy issues in the AG-UI overview and security pages.

Notes

• This intentionally avoids .NET package/API snippet changes while the AG-UI .NET SDK work is still in draft.

Validation

• git diff --check

[learn-build-service-prod]

Learn Build status updates of commit 762c087:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
agent-framework/get-started/workflows.md	⚠️Warning		Details
agent-framework/integrations/ag-ui/index.md	✅Succeeded
agent-framework/integrations/ag-ui/security-considerations.md	✅Succeeded

agent-framework/get-started/workflows.md

• Line 64, Column 1: [Warning: invalid-code] The code snippet "~/../agent-framework-code/python/samples/01-get-started/05_first_workflow.py" could not be found.
• Line 68, Column 1: [Warning: invalid-code] The code snippet "~/../agent-framework-code/python/samples/01-get-started/05_first_workflow.py" could not be found.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

[learn-build-service-prod]

Learn Build status updates of commit 6741f39:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
agent-framework/get-started/workflows.md	⚠️Warning		Details
agent-framework/integrations/ag-ui/index.md	✅Succeeded
agent-framework/integrations/ag-ui/security-considerations.md	✅Succeeded

agent-framework/get-started/workflows.md

• Line 64, Column 1: [Warning: invalid-code] The code snippet "~/../agent-framework-code/python/samples/01-get-started/05_first_workflow.py" could not be found.
• Line 68, Column 1: [Warning: invalid-code] The code snippet "~/../agent-framework-code/python/samples/01-get-started/05_first_workflow.py" could not be found.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

[learn-build-service-prod]

Learn Build status updates of commit 2f6a663:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
agent-framework/get-started/workflows.md	⚠️Warning		Details
agent-framework/integrations/ag-ui/index.md	✅Succeeded
agent-framework/integrations/ag-ui/security-considerations.md	✅Succeeded
agent-framework/integrations/ag-ui/testing-with-dojo.md	✅Succeeded

agent-framework/get-started/workflows.md

• Line 64, Column 1: [Warning: invalid-code] The code snippet "~/../agent-framework-code/python/samples/01-get-started/05_first_workflow.py" could not be found.
• Line 68, Column 1: [Warning: invalid-code] The code snippet "~/../agent-framework-code/python/samples/01-get-started/05_first_workflow.py" could not be found.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

[samjulien]

@microsoft-github-policy-service agree company="CopilotKit"