feat(provider): support Mimo Token Plan cluster switching

[ChouChiu]

What's Changed:

1. 支持 Mimo Token Plan 集群切换

本 PR 由 Mimo V2.5 Pro 完成，并已在本地测试

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Copilot’s Summary

This pull request adds support for selecting a region when configuring the "Mimo Token Plan" provider, allowing users to choose between China, Singapore, and Europe endpoints. It updates both the frontend and backend to handle the new region parameter, ensures proper recognition of all regional endpoints, and expands tests and translations accordingly.

Frontend and User Interface Enhancements:

• Added a region dropdown to the "Mimo Token Plan" provider setup in the settings panel, allowing users to select "China", "Singapore", or "Europe" as the endpoint region. The region selection is passed through the UI and bridge layer. [1] [2] [3] [4] [5] [6] [7]

Backend and API Changes:

• Modified backend logic to accept and process the region parameter for "Mimo Token Plan", using the correct API endpoint based on the selected region. This includes updates to officialProviderTemplate, AddOfficialProviderAccess, and related functions. [1] [2] [3] [4] [5] [6] [7]

Provider Recognition and Validation:

• Improved logic to recognize all valid "Mimo Token Plan" regional hosts throughout the codebase, including utility functions and provider kind checks. [1] [2] [3] [4]

Testing Improvements:

• Added and updated tests to verify correct handling of all regions for "Mimo Token Plan" providers, including endpoint URL selection, provider recognition, and vision capability. [1] [2] [3]

Localization:

• Updated English and Chinese (Simplified and Traditional) translations to include region labels for the new region selection feature. [1] [2] [3]