[Feature]: Add PHPStan Support alongside Psalm

[lotyp]

I propose adding PHPStan to our development toolchain alongside Psalm.

Key benefits include:

• Widespread Adoption: PHPStan is widely used in PHP projects, making integration seamless for most developers.
• Complementary Tooling: Using both PHPStan and Psalm allows us to leverage their unique strengths in static analysis, enhancing code quality and reliability. See the discussion here for more insights: GitHub Discussion #8986.
• Minimal Impact on Dependencies: Adding PHPStan should not significantly affect our dev dependencies, as buggregator/trap is included as a dev dependency.

This tool setup would increase the robustness of our code analysis without major overhead.