Add support for AI Translate Strings method

The Crowdin API now includes the **AI Translate Strings** endpoint in the AI section, allowing users to submit strings for AI-powered translation.

The Crowdin API client libraries should be updated to support this endpoint so developers can trigger AI string translation directly from SDKs.

**References:**
- [AI Translate Strings](https://support.crowdin.com/developer/api/v2/#tag/AI/operation/api.users.ai.translate.strings.post)

Start by reading the Crowdin API client's existing AI-related entry points and compare their request and response patterns with the linked AI Translate Strings endpoint. Done means the Go SDK exposes this endpoint so callers can submit strings for AI translation, with behavior aligned to the API reference.

Written by the indexing model from the issue text.