refactor: date accept number input

[xDivisionByZerox]

Reopen of #576 in favor of cleaner git history.

Created in relation to #394.

I changed the way dates are created from the Date.parse method to the Date.constructor since it uses that under the hood (MDN documentation).
Invalid dates were not handled before.

[xDivisionByZerox]

This history graph looks so much better :D

[codecov]

Codecov Report

Merging #670 (a041237) into main (7635dc9) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #670      +/-   ##
==========================================
- Coverage   99.34%   99.34%   -0.01%     
==========================================
  Files        1923     1923              
  Lines      176863   176856       -7     
  Branches      904      896       -8     
==========================================
- Hits       175706   175697       -9     
- Misses       1101     1103       +2     
  Partials       56       56              

Impacted Files	Coverage Δ
src/date.ts	100.00% <100.00%> (ø)
src/vendor/unique.ts	93.54% <0.00%> (-1.62%)	⬇️