Use number from author, instead the rounded number when replying

Current behavior.
Input: (-9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999.8)!

Output

The factorial of -10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034299354973207483343162971394820890205522474892993011626001538519429066631303722514983667773532306267617595032614012391853191680944494422987550150496295613569487222909477404251056153316311923288545965414068434237817967090934529974234116691935118663494850042764558583424564479128183955448593942350145823369526981855953014535503311699654509969940349220391197276009222211942005706127603611142640847667821805568 is ∞̃

The bot (probably) should post the original string of the number from the comment instead

Source: https://www.reddit.com/r/unexpectedfactorial/s/BUtgEsyFKX

Start by tracing how the bot parses the author’s numeric input and formats the factorial reply, using the example input and output in the issue as the reproduction case. Done means the reply preserves the original number string instead of the rounded value while retaining the expected factorial result.