Add semiliteral operator for expressions inside arrays and objects

[sargunv]

Description

The purpose of this PR is to add support for producing arrays with elements calculated by expressions. It's a draft implementation of #950.

I implemented it as a single semiliteral operator mirroring the literal syntax, like other lisps have quasiquote and quote. Happy to restructure this into []/{} or some other name as discussed in that design proposal.

Launch Checklist

• Confirm your changes do not include backports from Mapbox projects (unless with compliant license) - if you are not sure about this, please ask!
• Briefly describe the changes in this PR.
• Link to related issues.
• Write tests for all new functionality.
• Document any changes to public APIs.
• Post benchmark scores.
• Add an entry to CHANGELOG.md under the ## main section.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 90.90909% with 5 lines in your changes missing coverage. Please review.

Project coverage is 92.76%. Comparing base (c6fd205) to head (c4e7d47).
Report is 21 commits behind head on main.

Files with missing lines	Patch %	Lines
src/expression/definitions/semiliteral.ts	90.74%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #951      +/-   ##
==========================================
- Coverage   92.78%   92.76%   -0.03%     
==========================================
  Files         107      108       +1     
  Lines        4739     4794      +55     
  Branches     1346     1355       +9     
==========================================
+ Hits         4397     4447      +50     
- Misses        342      347       +5     

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[sargunv]

tweaked this because my Semiliteral class is abstract and therefore doesn't have a constructor. If we split semiliteral into two different classes with their own parse like the []/{} proposal, we can revert this line.

[louwers]

The idea is to link to issues in the MapLibre GL JS and MapLibre Native repo so that people can track progress on the implementation.

[HarelM]

@sargunv any updates on this? It seems that this PR is drifting away a bit...

[sargunv]

Ah yeah, I've been focused on maplibre native core stuff and haven't worked on this in a while. Last I remember, we aligned on this general approach in a monthly meeting in May, and next step was to write up some expression naming options and poll the community?

I'll propose some names with background/justification and share in Slack soon

[HarelM]

Yes, I think that was the last action item on this topic.