fix(provider/moonshotai): gate sampling by model (#19563)

## Summary

- omit `temperature`, `topP`, `frequencyPenalty`, and `presencePenalty`
from official Kimi model requests
- return actionable unsupported-setting warnings for omitted values
- preserve sampling controls for Moonshot V1 and unknown/custom model
IDs
- document model-specific sampling behavior

Fixes #19543

## Tests

- `pnpm --filter @ai-sdk/moonshotai test:node` (87 passed)
- `pnpm --filter @ai-sdk/moonshotai test:edge` (87 passed)
- `pnpm --filter @ai-sdk/moonshotai type-check`
- `pnpm type-check:full`
- `pnpm check`