Apply InstanceSupplier post-processing when bypassed by explicit args

[vlsi]

Summary

Fixes #35871.

When a bean definition has an InstanceSupplier with andThen() post-processing (as generated by AOT for @Autowired setter injection), calling getBean(name, args) bypasses the InstanceSupplier in createBeanInstance() but the andThen() post-processing was silently skipped. This meant that @Autowired setter injection would not be invoked for prototype beans retrieved with explicit constructor arguments in AOT mode.

This PR introduces InstanceSupplier#postProcessInstance() — a method that applies only the post-processing chain (registered via andThen()) to an already-created instance, without invoking the instance creation itself. AbstractAutowireCapableBeanFactory#doCreateBean() now calls this when it detects that the instance supplier was bypassed due to explicit args.

Changed files

• InstanceSupplier — new postProcessInstance(RegisteredBean, T) default method; the anonymous class returned by andThen() overrides it to chain through the after function.
• AbstractAutowireCapableBeanFactory — new hook applyInstanceSupplierPostProcessing() (no-op by default), called in doCreateBean() when args != null and an InstanceSupplier is present.
• DefaultListableBeanFactory — overrides applyInstanceSupplierPostProcessing() to delegate to InstanceSupplier#postProcessInstance().

Note for reviewers

The post-processing runs after addSingletonFactory() (early singleton caching). For the typical case where postProcessInstance() returns the same instance (e.g. setter injection), this is safe. If a custom andThen() returns a different object (wrapping), the existing circular reference detection at the end of doCreateBean() will detect the identity mismatch and throw BeanCurrentlyInCreationException — consistent with how Spring handles any BeanPostProcessor that changes bean identity. Reviewers may want to evaluate whether moving the post-processing before addSingletonFactory() would be preferable for the wrapping case, though that would diverge from the established pattern for other post-processors.

Test plan

• PrototypeWithArgsAotTests — end-to-end AOT test: prototype bean with @Autowired setter + BeanFactoryAware, retrieved via getBean(name, args) in a fresh AOT-compiled context
• DefaultListableBeanFactoryTests#singletonWithInstanceSupplierAndThenPostProcessingAppliedWithExplicitArgs — singleton bean with InstanceSupplier.andThen() + explicit args
• DefaultListableBeanFactoryTests#prototypeWithInstanceSupplierAndThenPostProcessingAppliedWithExplicitArgs
  — prototype bean with InstanceSupplier.andThen() + explicit args

🤖 Generated with Claude Code (Opus 4.6)
🤖 Cross-reviewed with Codex (GPT 5.4)