Add support for reading inheritors from a phpstan-sealed tag

[stof]

This improves interoperability for vendor libraries that are using phpstan. The @phpstan-sealed tag has the same semantic than @psalm-inheritors.

Closes #11510

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Note

Medium Risk
Updates docblock parsing to alias @phpstan-sealed into the inheritors constraint logic, which can change class/interface inheritance validation outcomes for existing codebases.

Overview
Adds interoperability with PHPStan’s @phpstan-sealed by mapping it to Psalm’s @psalm-inheritors during docblock parsing (via combined_tags).

Updates ClassLikeDocblockParser to read inheritors only from combined_tags, and extends the test suite to assert that extending a @phpstan-sealed base class triggers InheritorViolation the same way @psalm-inheritors does.

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