Fix: SupportedOption::isSupportedValue() fails after Redis deserialization

[chloe-pomegranate]

Summary

• Fixes SupportedOption::isSupportedValue() failing when AbstractEnum singletons are deserialized from a persistent object cache (Redis/Memcached)
• Normalizes AbstractEnum instances to their string ->value before comparison, so object identity (===) no longer breaks after unserialize()
• Adds tests verifying both scalar and array enum values survive serialize/unserialize round-trips

Closes #212

Test plan

• vendor/bin/phpunit --filter SupportedOptionTest — passing
• vendor/bin/phpcs --standard=phpcs.xml.dist src/Providers/Models/DTO/SupportedOption.php — clean
• vendor/bin/phpstan analyse src/Providers/Models/DTO/SupportedOption.php — no errors
• Verify on a WordPress site with Redis object cache that model discovery no longer fails after cache is populated

[github-actions]

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Co-authored-by: chloe-pomegranate <chloepomegranate@git.wordpress.org>
Co-authored-by: felixarntz <flixos90@git.wordpress.org>
Co-authored-by: saarnilauri <laurisaarni@git.wordpress.org>

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.45%. Comparing base (eb1241f) to head (cc6f1fd).
⚠️ Report is 3 commits behind head on trunk.

Additional details and impacted files

@@             Coverage Diff              @@
##              trunk     #213      +/-   ##
============================================
+ Coverage     87.41%   87.45%   +0.03%     
- Complexity     1189     1194       +5     
============================================
  Files            60       60              
  Lines          3846     3858      +12     
============================================
+ Hits           3362     3374      +12     
  Misses          484      484              

Flag	Coverage Δ
unit	87.45% <100.00%> (+0.03%)	⬆️

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[felixarntz]

@chloe-pomegranate Thank you for the PR, this looks excellent and implements the most suitable solution suggested in #212.

Appreciate you jumping in on this!

@saarnilauri Would be great if you could double check that this addresses the bug you reported in #212. Thank you!

[felixarntz]

Just an FYI for any future contributions: We normally use @since n.e.x.t everywhere, so that we can dynamically inject the actual version prior to a release.

But since this coming release is indeed going to be 1.2.1, this is good as is 👍

[saarnilauri]

@saarnilauri Would be great if you could double check that this addresses the bug you reported in #212. Thank you!

@felixarntz I can confirm that the fix addresses the bug. Thank you so much both of you!