feat: add MiniMax-M2-Stable model and enable prompt caching

[roomote]

Related GitHub Issue

Closes: #9070

Roo Code Task Context (Optional)

N/A - This PR was created by an automated workflow.

Description

This PR addresses the enhancement request to add the new MiniMax-M2-Stable model option and enable prompt caching support for MiniMax provider models.

Key implementation details:

• Added MiniMax-M2-Stable model configuration with identical technical specs to MiniMax-M2
• Enabled prompt caching for both MiniMax-M2 and MiniMax-M2-Stable models
• Set cache pricing according to MiniMax documentation (reads: /bin/sh.03/M tokens, writes: /bin/sh.375/M tokens)
• Updated model descriptions to distinguish between "Limited-time Free" (M2) and "High Concurrency, Commercial Use" (M2-Stable)
• Added comprehensive test coverage for the new model and caching features

Test Procedure

Automated Tests:

1. Run the MiniMax provider tests:

   cd src && npx vitest run api/providers/__tests__/minimax.spec.ts

2. Run TypeScript type checking:

   cd packages/types && npx tsc --noEmit

Manual Verification:

• The new MiniMax-M2-Stable model should appear in the model selection dropdown
• Prompt caching should be enabled for both MiniMax models
• Pricing information should reflect the correct cache read/write costs

All automated tests are passing (19 tests).

Pre-Submission Checklist

• Issue Linked: This PR is linked to an approved GitHub Issue (see "Related GitHub Issue" above).
• Scope: My changes are focused on the linked issue (one major feature/fix per PR).
• Self-Review: I have performed a thorough self-review of my code.
• Testing: New and/or updated tests have been added to cover my changes.
• Documentation Impact: I have considered if my changes require documentation updates (see "Documentation Updates" section below).
• Contribution Guidelines: I have read and agree to the Contributor Guidelines.

Screenshots / Videos

N/A - This is a backend change for model configuration.

Documentation Updates

• No documentation updates are required.

The changes are self-documenting through the model configuration and descriptions.

Additional Notes

This implementation follows the pricing and specifications provided in the MiniMax official documentation:

• https://platform.minimax.io/docs/guides/pricing
• https://platform.minimax.io/docs/api-reference/text-openai-api
• https://platform.minimax.io/docs/api-reference/text-anthropic-api

Feedback and guidance are welcome!

Get in Touch

N/A - Automated workflow

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Important

Add MiniMax-M2-Stable model and enable prompt caching for MiniMax models with updated tests.

• Models:
  • Add MiniMax-M2-Stable model to minimax.ts with specs identical to MiniMax-M2.
  • Enable prompt caching for MiniMax-M2 and MiniMax-M2-Stable with specific cache pricing.
  • Update model descriptions to reflect usage and pricing.
• Tests:
  • Add tests in minimax.spec.ts to verify MiniMax-M2-Stable configuration and prompt caching.
  • Ensure tests cover model selection, pricing, and caching behavior.

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[roomote]

Rooviewer   See task on Roo Cloud

Re-review complete. Latest changes look good - the description update is a minor documentation improvement with no functional impact.

The implementation correctly:

• Adds the MiniMax-M2-Stable model with identical specs to MiniMax-M2
• Enables prompt caching for both MiniMax models
• Updates pricing information according to MiniMax documentation
• Includes comprehensive test coverage for the new model
• Follows existing code patterns and type definitions

Previous reviews

• 7a93d2d: Review #1

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