feat(func): add FuncWithIndex and FuncWithIndexNoReturn

[quantumsheep]

Hey! I regularly write some functions that I pass to lo.Map and it's a hassle to have to pass the index every time.

Currently:

lo.Map(slice, func (v string, _ int) string {
	return doThing(v)
})

With the PR:

lo.Map(slice, lo.FuncWithIndex(doThing))

I'm not sure about the naming, it could simply be WithIndex.

I hope you like the idea.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.35%. Comparing base (efef0ff) to head (7b493bc).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #565      +/-   ##
==========================================
+ Coverage   94.33%   94.35%   +0.01%     
==========================================
  Files          17       17              
  Lines        2790     2798       +8     
==========================================
+ Hits         2632     2640       +8     
  Misses        154      154              
  Partials        4        4              

Flag	Coverage Δ
unittests	94.35% <100.00%> (+0.01%)	⬆️

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[itroot]

Wow. also faced that issue, and made a quite similar solution:

• Curried map, reduce and filter for partial application  #330 (comment)

[quantumsheep]

Wow. also faced that issue, and made a quite similar solution:

* [Curried map, reduce and filter for partial application  #330 (comment)](https://github.com/samber/lo/issues/330#issuecomment-2507770542)

Glad to see I'm not the only one wanting a feature like this :)