feat: add LiteralValue::Int8 and Int16

[ugoa]

closes #3365

[codspeed-hq]

CodSpeed Performance Report

Merging #3736 will improve performances by 47.91%

_{Comparing ugoa:DAFT-3365-add-literalvalue-int8-int16 (5613e6e) with main (a8d63dd)}

Summary

⚡ 2 improvements
✅ 25 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	test_count[1 Small File]	3.9 ms	3.4 ms	+16.73%
⚡	test_show[100 Small Files]	23.5 ms	15.9 ms	+47.91%

[codecov]

Codecov Report

Attention: Patch coverage is 36.58537% with 52 lines in your changes missing coverage. Please review.

Project coverage is 77.55%. Comparing base (a8d63dd) to head (5613e6e).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/daft-dsl/src/lit.rs	41.09%	43 Missing ⚠️
src/daft-sql/src/modules/numeric.rs	0.00%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3736      +/-   ##
==========================================
- Coverage   77.58%   77.55%   -0.04%     
==========================================
  Files         729      729              
  Lines       92035    92116      +81     
==========================================
+ Hits        71409    71440      +31     
- Misses      20626    20676      +50     

Files with missing lines	Coverage Δ
src/daft-algebra/src/simplify.rs	77.34% <ø> (ø)
src/daft-sql/src/modules/numeric.rs	78.43% <0.00%> (-4.91%)	⬇️
src/daft-dsl/src/lit.rs	55.42% <41.09%> (-2.82%)	⬇️

... and 1 file with indirect coverage changes

[universalmind303]

looks good to me. thanks @ugoa

[ugoa]

Oh wow, thanks for accepting the PR!