[ENHANCEMENT] The Minimax provider has added a model option and prompt caching.

[nokaka]

Problem (one or two sentences)

The Minimax provider has added a model option and prompt caching.

Model	Description	Input	Output	Prompt caching Read	Prompt caching Write
MiniMax-M2	Limited-time Free	$0.3 / M tokens	$1.2 / M tokens	$0.03 / M tokens	$0.375 / M tokens
MiniMax-M2-Stable	High Concurrency, Commercial Use	$0.3 / M tokens	$1.2 / M tokens	$0.03 / M tokens	$0.375 / M tokens

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

Context (who is affected and when)

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Desired behavior (conceptual, not technical)

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Constraints / preferences (optional)

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Request checklist

• I've searched existing Issues and Discussions for duplicates
• This describes a specific problem with clear context and impact

Roo Code Task Links (optional)

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Acceptance criteria (optional)

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Proposed approach (optional)

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Trade-offs / risks (optional)

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[roomote]

I'm exploring a potential fix for adding the new MiniMax-M2-Stable model option and prompt caching support. I'll open a PR to share progress.

[roomote]

Opened PR #9072 with my attempt at addressing this issue.

The implementation adds:

• ✅ MiniMax-M2-Stable model for high concurrency/commercial use
• ✅ Prompt caching support enabled for both models
• ✅ Correct pricing for cache reads (/bin/sh.03/M) and writes (/bin/sh.375/M)
• ✅ Full test coverage with all tests passing

All CI checks are passing. Feedback welcome!

PR: #9072