fix: terminate wildcard erasure lookup

[martinfrancois]

Summary

Prevent recursive type erasure when Spoon resolves a bounded wildcard in no-classpath mode.

Fixes #6802.

Problem

Type erasure is the simpler type Spoon uses when it compares generic method or constructor signatures. For a parameter such as ? extends E, Spoon tried to compute that type by finding a declaration named ?. Resolving the bound E then requested the containing method declaration. Matching that method erased the same wildcard parameter again, so the cycle repeated until a StackOverflowError occurred.

Change

• Erase an upper-bounded wildcard to the erasure of its bound.
• Erase a lower-bounded wildcard to Object.
• Guard executable matching against re-entering the same executable reference through nested or sibling type parameters.
• Traverse paired return, parameter, declaring, wildcard, array, and generic-argument types with one ordered worklist, preserving the existing first-match order.
• After exact method or constructor lookup succeeds, follow the reference's array, wildcard, declaring-type, and generic-argument path to the corresponding nested declaration.
• Keep the surrounding lexical declaration for references created from a lexical type parameter, including after reparenting, cloning, and model serialization.
• Identify parsed declaration owners by source location rather than mutable method or type names, and retain the owner marker when the model is cloned or serialized.
• Resolve unnamed in-memory source files through Spoon's compilation-unit cache so the same declaration keeps one stable owner.
• Preserve intentional not-found results in declaration lookup helpers while satisfying the repository's Qodana requirements.

Validation

• Added a reduced no-classpath regression that produces a StackOverflowError before the fix and terminates after the fix.
• mvn -q -Dtest=spoon.test.reference.TypeParameterErasureRecursionTest test passes all 24 focused tests, including positionless overloads, renamed parsed methods and types, direct-bound reparenting, cloning, serialization, and unnamed in-memory sources.
• mvn -q -Dtest=spoon.test.generics.GenericsTest,spoon.test.reference.TypeReferenceTest test passes all 96 tests.
• mvn -q verify passes with 16 skipped and no failures or errors.
• As a compatibility replay, StoneDetector processes the historical Elasticsearch AttributeMap.java: AST 1/1, CFG 5/5, dominators 5/5, paths 5/5, and no reported errors. That full file also passes on the audited upstream base, so the reduced regression above is the discriminating evidence.
• All 14 GitHub checks pass, including the main Qodana check and the Java 17, 21, and 25 test matrix.