Improve Data Quality and Radius Functionality in FastMode

When activating FastMode, the returned data is significantly limited, with many data points missing. Additionally, the `radius` property does not function as expected when FastMode is inactive.

The current behavior creates the following challenges:

FastMode: Returns a small amount of data, which is often incomplete or of poor quality.
Standard Mode: Provides richer data but does not restrict results to the specified radius, making it unreliable for targeted queries.
The desired functionality is to:

Obtain rich, complete data within a specified radius.
Ensure that the radius property works consistently, regardless of whether FastMode is active or not.
This improvement would greatly enhance data accuracy and usability for targeted searches.

Thank you!

Start by locating the FastMode and radius handling entry points in the Go scraper. Compare returned data and radius filtering in both FastMode and standard mode, then verify that both modes provide complete results restricted to the requested radius.

Written by the indexing model from the issue text.