Previously, `{{$randomInt}}` returned values across the full JavaScript number range.
This commit updates the generator to produce integers between 0 and 1000,
matching the documented behavior.
Fixes#4847
* move interpolateMockVars function inside the main interpolate logic inside bruno-common.
* improve comments for JSON escaping logic in interpolate function
* update faker-functions to use CommonJS module syntax to satisfy jest and add regex validation tests
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Co-authored-by: sanjai0py <sanjailucifer666@gmail.com>
Co-authored-by: ramki-bruno <ramki@usebruno.com>