[FEAT] Consolidate to list namespace

[jaychia]

Closes: #1056

• Consolidates on using .list as the namespace on both Series and Expression list operations
• As a driveby, exposes the .list.lengths() expression (the functionality on a Series was already implemented)

[codecov]

Codecov Report

Merging #1180 (138fde4) into main (355e494) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1180   +/-   ##
=======================================
  Coverage   88.43%   88.44%           
=======================================
  Files          54       54           
  Lines        5562     5564    +2     
=======================================
+ Hits         4919     4921    +2     
  Misses        643      643           

Impacted Files	Coverage Δ
daft/expressions/expressions.py	91.78% <100.00%> (+0.04%)	⬆️
daft/series.py	92.09% <100.00%> (ø)