Clarification about retirement/deprecation of Azure OpenAI On Your Data Extension

The latest model that Azure OpenAI's On-Your-Data extension supports is GPT-4o ([link](https://learn.microsoft.com/en-us/azure/ai-foundry/openai/concepts/use-your-data?view=foundry-classic&tabs=ai-search%2Ccopilot#regional-availability-and-model-support)). Considering gpt-4o (2024-11-20) is retiring on 2026-06-03,
- There needs to be a declaration if On-Your-Data is also retiring on that date.
- If yes, there needs to be a **documented migration path** from On-Your-Data to Foundry-Agent-Service.

There are some discussions happening on different repositories ([one](https://github.com/Azure/azure-sdk-for-net/issues/52539#issuecomment-3749833333), [two](https://github.com/microsoft/semantic-kernel/issues/12865#issuecomment-3718241696): closed issue). Hence, creating a new issue here.

Open queries about the topic of migration:
- Looks like On-Your-Data works with gpt-4.1, gpt-4.1-mini although the relevant documentation states that these two models are not supported ([one](https://github.com/Azure/azure-sdk-for-net/issues/52539#issuecomment-3749833333), [two](https://github.com/Azure/azure-sdk-for-net/issues/52539#issuecomment-3767255478)). In case, gpt-4.1 is declared as a supported model, the retirement date for On-Your-Data shifts to 2026-10-14 (4.1 retirement date) from 2026-06-03 (4o retirement date).
- In the other thread, Foundry Agent Service (new) along with Foundry IQ/Azure AI Search Tool has been recommended as the alternative for On-Your-Data ([link](https://github.com/microsoft/semantic-kernel/issues/12865#issuecomment-3721566037)). However,
- The **Azure AI Projects client library for Python** exposing the **Responses API** is still in **Beta** (`2025-11-15-preview`)
Reference: [link](https://learn.microsoft.com/en-us/python/api/overview/azure/ai-projects-readme?view=azure-python-preview&preserve-view=true#performing-responses-operations-using-openai-client)

- **Foundry IQ** is also in **Beta**
Reference: [link](https://learn.microsoft.com/en-us/azure/ai-foundry/agents/how-to/tools/knowledge-retrieval?view=foundry&tabs=foundry%2Cpython)

Considering the there is lesser than 6 months of time for the migration and not all the services/APIs are not in GA/Stable, a quick response would be appreciated.

cc: @lindazqli, @sarah-widder