add BrowserRun types

[Refaerds]

Summary

Adds TypeScript type definitions for the existing browser binding:

• BrowserRun — abstract class with fetch() and overloaded quickAction() method supporting 8 action types
• Action-specific option types: BrowserRunScreenshotOptions, BrowserRunPDFOptions, BrowserRunScrapeOptions, BrowserRunLinksOptions, BrowserRunSnapshotOptions, BrowserRunJsonOptions, BrowserRunMarkdownOptions, BrowserRunContentOptions
• Quick action response types: BrowserRunContentSuccessResponse, BrowserRunLinksSuccessResponse, BrowserRunScrapeSuccessResponse, BrowserRunSnapshotSuccessResponse, BrowserRunJsonSuccessResponse, BrowserRunMarkdownSuccessResponse, BrowserRunErrorResponse, BrowserRunJsonErrorResponse

[github-actions]

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[Refaerds]

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