Enhancement: Document array shapes

[localheinz]

This pull request

• [x] documents array shapes
• [x] runs tools/psalm --config=.psalm/config.xml --set-baseline=.psalm/baseline.xml

[codecov[bot]]

Codecov Report

Merging #991 (c76d15e) into main (ef1c71e) will decrease coverage by 0.10%. The diff coverage is n/a.

:exclamation: Current head c76d15e differs from pull request most recent head 122df62. Consider uploading reports for the commit 122df62 to get more accurate results

@@             Coverage Diff              @@
##               main     #991      +/-   ##
============================================
- Coverage     85.18%   85.08%   -0.10%     
- Complexity     1177     1178       +1     
============================================
  Files            69       69              
  Lines          4145     4151       +6     
============================================
+ Hits           3531     3532       +1     
- Misses          614      619       +5     

Impacted Files	Coverage Δ
src/CodeCoverage.php	50.00% <ø> (-0.84%)	:arrow_down:
src/Data/ProcessedCodeCoverageData.php	100.00% <ø> (ø)
src/Data/RawCodeCoverageData.php	89.88% <ø> (ø)
src/Driver/XdebugDriver.php	42.85% <ø> (ø)
src/Node/AbstractNode.php	87.50% <ø> (ø)
src/Node/Builder.php	97.77% <ø> (ø)
src/Node/Directory.php	92.71% <ø> (ø)
src/Node/File.php	80.93% <ø> (ø)
src/Report/Xml/Tests.php	100.00% <ø> (ø)
src/StaticAnalysis/CachingFileAnalyser.php	0.00% <ø> (ø)
... and 3 more

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