fix: support higher-order method calls on expectations

[imKenjo18]

Fixes pestphp/pest#1896

Problem

When chaining method calls directly on an expectation:

$policy = new UserPolicy;

expect($policy)
    ->view()->toBeTrue()
    ->update()->toBeTrue();

It causes two PHPStan errors:

• Call to an undefined method Pest\Expectation<UserPolicy>::view()
• Calling toBeTrue() on Expectation<UserPolicy>; assertion is impossible.

Solution

• Type Inference (HigherOrderExpectationTypeExtension & ExpectationChainStateResolver):
  • Resolves higher-order method return types from the underlying value type (TValue).
  • Correctly resets the target back to the original value type after intermediate assertions (toBeTrue(), etc.).
  • Returns MixedType wrapped in HigherOrderExpectation when methods are unresolvable or reflection fails to ensure chain stability.
• Typo & Undefined Method Handling (HigherOrderExpectationMethodIgnoreExtension):
  • Implements IgnoreErrorExtension to ignore method.notFound only if the method exists on TValue.
  • Typos and invalid calls (e.g. expect($post)->typoMethod() or expect('string')->foo()) are properly reported as errors by PHPStan.

[MrPunyapal]

Tests pass locally. The main case is fixed. Requesting small changes below.

src/Type/Pest/ExpectationMethodsExtension.php
hasMethod returns true for any method name. I checked and expect($post)->typoMethod() no longer errors. Same for expect('string')->foo(). Can we only skip the error when the method exists on the value type? Right now typos are hidden.

src/Type/Pest/HigherOrderExpectationTypeExtension.php
When the method is missing you return null. When getMethod throws you return Mixed wrapped in HigherOrderExpectation. Pick one. I think wrap in Mixed in both cases so the chain type stays the same.

tests/Type/data/higher-order-expectations.php
Please add the exact case from the issue. One method plus toBe is covered. Missing is method plus toBe plus method again:
expect($policy)->view()->toBeTrue()->update()->toBeTrue()
That is what broke before. Without it the reset logic is not tested.

src/Type/Pest/PestConfigReader.php
src/Type/Pest/PestHookPropertyReader.php
These ??= changes are unrelated to this fix. Please remove them from this PR or split them out.

src/Type/Pest/ExpectationMethodReflection.php
This accepts any args and returns Mixed. So wrong args like typedMethod('string') for int param pass silently. Same for protected methods. I am ok to keep it for now since properties work the same way, but please note it as a limit or follow up.

Style:
Run pint on the new files. There are spacing and brace issues in the new extension files.

[imKenjo18]

@MrPunyapal, I have updated the PR as per your comment.

I reverted the rector fixes as it was out of scope and will probably submit another PR for that.

Sorry for the mess, still learning how everything works. 😅