Allow customizing the "Test Request" button label

Currently the "Test Request" button in the API client panel has a hardcoded label. For documentation targeting production APIs — where clicking the button sends a real request, not a sandboxed test — the word "Test" is misleading and can cause confusion.

Feature request: Allow the button label to be configured, either:

• Via scalar.config.json (e.g. a localization.translations key), or
• A dedicated requestButtonLabel config option

Example use case: A label like "Run Request" or "Send Request" better communicates that the action executes against a live production API, not a mock or test environment. This is especially important for APIs where a single call can trigger real-world side effects (order processing, inventory changes, etc.).

---

This issue was written with the assistance of an AI (Claude) on behalf of a Scalar Docs user.