[Feature] Copilot (M365) Support

[Handyfff]

Please add the M365 Copilot support. It offers to choose GPT 5.5 unlike the usual copilot.

This is a different product from Copilot

https://m365.cloud.microsoft/

[PRIYESHSINGH24]

Feature Request: Add Microsoft 365 Copilot Support

Description

Please add support for Microsoft 365 Copilot (https://m365.cloud.microsoft/).

This is a different product from the standard Copilot and provides access to additional model options such as GPT-5.5 selection.

Currently, the existing Copilot integration does not properly work with M365 Copilot sessions/accounts.

Expected Behavior

• Detect and support m365.cloud.microsoft
• Support GPT-5.5 model selection available in M365 Copilot
• Handle authentication/session flow separately from standard Copilot if required

Additional Context

M365 Copilot behaves differently from the regular Copilot product, so treating them as the same service causes compatibility issues.

I can help with testing if needed.
@pk8898 @Handyfff @Zen4-bit