docs: Improve API documentation

[cbaker6]

New Pull Request Checklist

• I am not disclosing a vulnerability.
• I am creating this PR in reference to an issue.

Issue Description

Improve API documentation and build using xcodebuild instead of SPM.

Related issue: #n/a

Approach

Build using xcodebuild.

TODOs before merging

• Add entry to changelog
• Add changes to documentation (guides, repository pages, in-code descriptions)

[codecov]

Codecov Report

Merging #253 (8f9d16f) into main (ee67405) will decrease coverage by 0.23%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #253      +/-   ##
==========================================
- Coverage   76.66%   76.43%   -0.24%     
==========================================
  Files          99       99              
  Lines       10351    10351              
==========================================
- Hits         7936     7912      -24     
- Misses       2415     2439      +24     

Impacted Files	Coverage Δ
Sources/ParseSwift/Objects/ParseObject.swift	75.42% <ø> (ø)
Sources/ParseSwift/Internal/Data+hexString.swift	40.00% <0.00%> (-60.00%)	⬇️
Sources/ParseSwift/Coding/ParseEncoder.swift	73.25% <0.00%> (-0.36%)	⬇️

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