Added a new method to check for Xiaomi MiMo thinking mode and updated the reasoning checks.

What does this PR do?

When Hermes falls back from a non-thinking provider (e.g. Vertex Gemini) to Xiaomi MiMo in thinking mode, all subsequent API calls to MiMo fail with HTTP 400:

"The reasoning_content in the thinking mode must be passed back to the API."

The conversation is permanently broken until /reset.

_needs_thinking_reasoning_pad() only recognizes DeepSeek and Kimi/Moonshot as providers that enforce reasoning_content echo-back. Xiaomi MiMo (mimo-v2.5-pro in thinking mode) has the same requirement but is not listed. This PR adds MiMo detection to fix the issue.

Related Issue

Fixes # (no issue created yet)

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 🔒 Security fix
• 📝 Documentation update
• ✅ Tests (adding or improving test coverage)
• ♻️ Refactor (no behavior change)
• 🎯 New skill (bundled or hub)

Changes Made

• run_agent.py: Added _needs_mimo_tool_reasoning() method to detect Xiaomi MiMo thinking mode providers (by provider name, model name, and xiaomimimo.com base URL)
• run_agent.py: Updated _needs_thinking_reasoning_pad() to include _needs_mimo_tool_reasoning() in its check

How to Test

1. Set primary model to Vertex Gemini, fallback to MiMo (mimo-v2.5-pro via custom provider with xiaomimimo.com base URL)
2. Send a message that triggers rate-limit on Gemini (HTTP 429)
3. Hermes falls back to MiMo — subsequent calls should succeed instead of failing with HTTP 400
4. Verify that conversation history with mixed providers (Gemini + MiMo) replays correctly to MiMo

Reproduction (before fix)

1. Configure fallback chain: primary = Vertex Gemini, fallback = MiMo (mimo-v2.5-pro)
2. Trigger Gemini rate-limit (429)
3. Hermes falls back to MiMo
4. Next call fails with: HTTP 400: "The reasoning_content in the thinking mode must be passed back to the API."
5. Conversation is permanently broken until /reset

After fix

Same steps as above — step 4 succeeds, conversation continues normally.

Checklist

Code

• I've read the Contributing Guide
• My commit messages follow Conventional Commits (fix(scope):, feat(scope):, etc.)
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this fix/feature (no unrelated commits)
• I've run pytest tests/ -q and all tests pass
• I've added tests for my changes (required for bug fixes, strongly encouraged for features)
• I've tested on my platform: Linux (GCP Ubuntu)