[TomasVotruba]

Fixes #8493.

A child class's refactoring result can depend on its parent/interface/trait (e.g. AddReturnTypeDeclarationBasedOnParentClassMethodRector, ReturnTypeFromStrictTypedCallRector, AddOverrideAttributeToOverriddenMethodsRector). The cache keyed each file only by its own contents, so when an ancestor changed and the child did not, the child's entry still looked valid - it was skipped and the transformation it now needed was silently missed.

Fix

• FileDependencyResolver resolves the ancestry files (parents, interfaces, traits) a file relies on, via reflection. Best-effort: resolving ancestors can throw on malformed/unresolvable classes, and a miss there only skips a cache optimisation, so it is caught and ignored.
• When a clean file is cached, ChangedFilesDetector also stores the content hash of each ancestry file under a separate key. hasFileChanged() reports the file as changed when its own hash matches but any stored ancestor hash no longer does (or the ancestor file disappeared).

Scope

Covers class-ancestry dependencies, which are the cases reported in the issue. It does not track arbitrary cross-file dependencies (a called function's file, a referenced constant); that would need a full dependency graph and is out of scope here.

Tests

• CacheFileDependencyTest - end-to-end: a cached child is reconsidered after its parent gains a return type.
• FileDependencyResolverTest - unit: the resolver returns the parent file, and nothing for an ancestor-less class.
• Full suite green.

Note

Extra reflection + ancestor-hash work runs per clean cached file, so warm runs do slightly more work. Correctness-first; happy to run a full warm-run A/B against main if wanted before merge.