Accurate sizes: Get accurate sizes base on ancestor block context

[mukeshpanchal27]

Summary

• Introduces an initial proof of concept (POC) to return accurate sizes based on ancestor block context.
• This PR does not address all the use cases described in Incorporate layout constraints from ancestor blocks into the sizes calculations #1511.
• Includes some unit tests that may require updates or extensions.
• Additional unit tests will be added in future iterations.

See #1511

[codecov]

Codecov Report

Attention: Patch coverage is 96.42857% with 1 line in your changes missing coverage. Please review.

Project coverage is 57.77%. Comparing base (2c31b95) to head (ff1a7f2).

Files with missing lines	Patch %	Lines
...ns/auto-sizes/includes/improve-calculate-sizes.php	96.42%	1 Missing ⚠️

Additional details and impacted files

@@                      Coverage Diff                       @@
##           add/ancestor-block-context    #1818      +/-   ##
==============================================================
+ Coverage                       57.53%   57.77%   +0.24%     
==============================================================
  Files                              84       84              
  Lines                            6544     6567      +23     
==============================================================
+ Hits                             3765     3794      +29     
+ Misses                           2779     2773       -6     

Flag	Coverage Δ
multisite	57.77% <96.42%> (+0.24%)	⬆️
single	34.97% <96.42%> (+0.32%)	⬆️

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[mukeshpanchal27]

@joemcgill This one ready for your review.