feat: add Kimi K2 thinking model to VertexAI provider

[roomote]

This PR attempts to address Issue #9268. Feedback and guidance are welcome.

Changes

• Added moonshotai/kimi-k2-thinking-maas model to the VertexAI provider configuration
• Configured with 256K context window (262,144 tokens for both max and context)
• Set pricing: $0.60 per million input tokens, $2.50 per million output tokens
• Model description: "Kimi K2 Thinking Model with 256K context window."

Testing

• TypeScript compilation passes without errors
• Linting checks pass
• No existing tests found for vertex models specifically

Closes #9268

---

Important

Add moonshotai/kimi-k2-thinking-maas model to vertexModels in vertex.ts with specific configuration and pricing.

• Model Addition:
  • Added moonshotai/kimi-k2-thinking-maas to vertexModels in vertex.ts.
  • Configured with 16,384 max tokens and 262,144 context window.
  • Pricing set at $0.60 per million input tokens and $2.50 per million output tokens.
  • Description: "Kimi K2 Thinking Model with 256K context window."
• Testing:
  • TypeScript compilation and linting checks pass.
  • No specific tests for vertex models found.
• Issue Closure:
  • Closes [ENHANCEMENT] Request to add Kimi K2 thinking to Google VertexAI provider #9268.

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[roomote]

Rooviewer   See task on Roo Cloud

Review complete. The implementation correctly adds the Kimi K2 thinking model to VertexAI with proper configuration. All previously flagged issues have been resolved.

• Update maxTokens from 262_144 to 16_384 per maintainer request

Previous reviews

• df3074b: Review #1
• df3074b: Review #2

_{Mention @roomote in a comment to request specific changes to this pull request or fix all unresolved issues.}

[nitishchauhan0002]

Guys, @mrubens @cte @jr Hope you're all doing well!
When you get a chance, could you please review the PR and proceed with the merge if everything looks good?

I'd really appreciate your support on this. Thank you in advance for your time and help!

[hannesrudolph]

@roomote set the maxTokens to 16_384

[roomote]

Rooviewer   See task on Roo Cloud

Review complete. Found 1 issue that needs to be addressed before merging.

• Update maxTokens from 262_144 to 16_384 per maintainer request

_{Mention @roomote in a comment to request specific changes to this pull request or fix all unresolved issues.}

[roomote]

Fixaroo   See task on Roo Cloud

Updated maxTokens from 262_144 to 16_384 for the Kimi K2 model as requested.

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