Since arbitrary levels of proxies do not occur, this commit replaces
the `while` loop in SerializableTypeWrapper.unwrap() with a simple
`if` statement.

Closes gh-23415

Since Java 8, putIfAbsent() is a standard method in java.util.Map. We
therefore no longer need the custom implementation that overrides the
standard implementation in HashMap.

Prior to this commit, AnnotationAttributes#assertNotException checked if
the attribute value was an instance of Exception. Although this was
typically sufficient, the scope was not always broad enough -- for
example, if AnnotationReadingVisitorUtils#convertClassValues stored a
Throwable in the map (such as a LinkageError).

This commit fixes this by checking for an instance of Throwable in
AnnotationAttributes#assertNotException.

Closes gh-23424

Closes gh-23420

Optimize section headings for dispaly in left hand navigation.

Closes gh-23401

See gh-23346

Closes gh-23359

See gh-23345

We now reuse interfaces for EntityManager and Query classes that
are proxied through ExtendedEntityManagerCreator and SharedEntityManagerCreator.

These caches prevent excessive object allocations through
ClassUtils.getAllInterfacesForClass(…) and
ClassUtils.getAllInterfacesForClassAsSet(…).

Closes gh-23349

Closes gh-23346

Closes gh-23352

See gh-23385

Includes consistent use of getContainingClass()

* 22391_conditional_view_caching:
  Polish contribution
  Add filter to AbstractCachingViewResolver

See gh-22606

This commit introduces a filter that specifies whether a View should be
cached by the AbstractCachingViewResolver or not.

Closes gh-22391

* pr/23394:
  Polish getTypeForFactoryBean comment

Closes gh-23394

See gh-23394