Add more benchmarks, smoke tests, make FilterVar serializable

[alganet]

This commit introduces a new feature test: SerializableTest, that
tests several validators for their ability to be serialized and
unserialized.

It also makes it so that the same list of validators can be used
by both simple benchmarks and "smoke tests" of all kinds, including
this serialize/unserialize one.

Additionally, the FilterVar validator was modified. Previously, due
to the use of Callback, it was not serializable, but now it is.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.78%. Comparing base (8e5938a) to head (558d5ca).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1607      +/-   ##
============================================
+ Coverage     97.51%   97.78%   +0.27%     
- Complexity     1006     1011       +5     
============================================
  Files           212      213       +1     
  Lines          2334     2351      +17     
============================================
+ Hits           2276     2299      +23     
+ Misses           58       52       -6     

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[Copilot]

Pull request overview

This PR enhances testing infrastructure by consolidating validator test data into a reusable trait, adding comprehensive benchmarks, and making the FilterVar validator serializable.

Changes:

• Introduced SmokeTestProvider trait with comprehensive validator test data for reuse across benchmarks and serialization tests
• Added serialization test coverage to verify validators can be serialized and deserialized
• Refactored FilterVar from extending Envelope to directly implementing Validator to support serialization

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/library/SmokeTestProvider.php	New trait providing test data for all validators, enabling reuse across different test types
tests/unit/SerializableTest.php	New test verifying validators can be serialized/unserialized while maintaining functionality
tests/benchmark/ValidatorBench.php	Refactored to use SmokeTestProvider, expanding benchmark coverage from ~50 to ~150 validators
phpbench.json.dist	Updated bootstrap path to use tests/bootstrap.php for proper test environment setup
library/Validators/FilterVar.php	Refactored to implement Validator directly instead of extending Envelope for serialization support

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[henriquemoody]

I would be great if you could add the information you have in the pull request to the commit message, it helps with adding more context when looking at the git logs.

Personally, I prefer when the commit tells what it does in the subject line, and explain why in the body. This subject line tells 3 different things, and it would be best to have a subject line that expresses (in imperative mood) the overarching subject of the commit.

[henriquemoody]

My comments are mostly cosmetic, but the place where that test is, I think we should really change.