feat: Add missing gradient functions

[Aiving]

Closes #773, also closes #774

[codecov]

Codecov Report

Attention: Patch coverage is 67.21311% with 100 lines in your changes missing coverage. Please review.

Project coverage is 73.90%. Comparing base (c3821a3) to head (9b55129).
Report is 2 commits behind head on main.

Files	Patch %	Lines
crates/state/src/values/gradient.rs	44.27%	73 Missing ⚠️
crates/core/src/elements/rect.rs	0.00%	18 Missing ⚠️
crates/state/src/values/fill.rs	33.33%	4 Missing ⚠️
crates/core/src/node.rs	0.00%	3 Missing ⚠️
crates/devtools/src/tabs/style.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #776      +/-   ##
==========================================
- Coverage   73.94%   73.90%   -0.05%     
==========================================
  Files         201      201              
  Lines       21172    21453     +281     
==========================================
+ Hits        15655    15854     +199     
- Misses       5517     5599      +82     

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[Aiving]

@marc2332 I think it is now ready for workflow approval and, if all goes well, for review too.

[marc2332]

LGTM. Could you update the gradient example to showcase the new two methods tho?

[Aiving]

Oh, okay!

[Aiving]

LGTM. Could you update the gradient example to showcase the new two methods tho?

done!

[marc2332]

I was thinking about having 1 example instead of 3 hehe

[Aiving]

I was thinking about having 1 example instead of 3 hehe

done!