'1,000,000 days ago' parses as the current time; thousands separators truncate the relative number

A number with a thousands separator parses as a much smaller relative date. With two separators it comes back as the base time.

from datetime import datetime
import dateparser

base = datetime(2024, 6, 15, 12, 0, 0)
S = {"RELATIVE_BASE": base}

dateparser.parse("1000 days ago", settings=S)        # 2021-09-19  correct
dateparser.parse("1,000 days ago", settings=S)       # 2024-06-14  one day
dateparser.parse("12,345 days ago", settings=S)      # 2024-06-03  12.345 days
dateparser.parse("1,000,000 days ago", settings=S)   # 2024-06-15 12:00, the base, unchanged

The first three follow from float(num.replace(",", ".")) in get_kwargs, and #876 added that on purpose so "1,5 hours" works. That should stay. In a locale where the comma is a decimal mark those readings are right, and there is no locale information at that point to tell the two apart.

The last one is different. Translation rewrites the string first:

"1,000,000 days ago"  ->  "1 000,000 day ago"
PATTERN.findall       ->  [(" 000,000", "day")]
float("000.000")      ->  0.0

The leading 1 is dropped, not misread. The \s* in ([+-]?\s*\d++[.,]?\d*+), which is there for "+ 5 days", lets the match start partway through the number. No reading of "1,000,000 days ago" gives the current time, so this one is wrong in every locale.

Worth deciding together, since a fix for the second probably settles the first. The options I can see are to use the detected locale for the separator, treat a separator followed by exactly three digits as grouping, or fail instead of returning a truncated number. Happy to send a patch once you say which way you want it.

Start by reproducing the examples with RELATIVE_BASE, then inspect get_kwargs and the translation step before PATTERN.findall. Trace how the \s* in the numeric pattern handles grouped numbers and compare the existing comma-decimal behavior. Done means the multi-separator case cannot silently truncate or return the unchanged base time, while the intended decimal behavior remains covered.