Rollup merge of #128641 - Konippi:standardize-duplicate-processes-in-parser, r=scottmcm

refactor: standardize duplicate processes in parser

## Summary
This PR refactors the `read_number` function to standardize duplicate code, improve readability, and enhance efficiency.

## Changes
- Merged the logic for both `max_digits` cases into a single `read_atomically` closure
- Simplified control flow and reduced code duplication

Author: matthiaskrgr