Closes gh-21798

Closes gh-21317

See gh-21776

See gh-21775

See gh-21774

See gh-21784

See gh-21782

See gh-21779

Closes gh-21739

See gh-21783

 See gh-21781

See gh-21778

Closes gh-21738

See gh-21780

See gh-21777

Closes gh-21729

Closes gh-21786

Previously, when lazy initialization was enabled, STOMP-based WebSocket
messaging would not work as the stompWebSocketHandlerMapping bean was
not initialized and CONNECT requests would go unanswered.

This commit adds a LazyInitializationExcludeFilter that causes the
stompWebSocketHandlerMapping bean to always be initialized eagerly.
This triggers initialization of the WebSocket transport allowing
requests to be received and processed.

Fixes gh-19611

Closes gh-21731

Closes gh-21730

Closes gh-21728

* gh-21702:
  Improve tests for BasicErrorController
  Fix BasicErrorController include parameter parsing

Closes gh-21702

This commit improves the tests for BasicErrorController by decoupling
coverage for the include-message and include-binding-errors
parameters to ensure the options operate properly independent of
each other.

See gh-21702

This commit fixes an error in BasicErrorController where the wrong
property was referenced for binding error inclusion.

See gh-21702

Closes gh-21695

* pr/21060:
  Polish 'Fix Mustache to not ignore native fetcher'
  Fix Mustache to not ignore native fetcher

Closes gh-21060

See gh-21060

Alter the logic of `MustacheEnvironmentCollector` so that the
native fetcher is always consulted if it exists.

When the context is a map (as it is in a web View for instance) you
can't assume a non-null fetcher actually contains the property you are
searching for.

See gh-21060

* pr/21650:
  Polish 'Clarify documentation for probe ports'
  Clarify documentation for probe ports

Closes gh-21650

See gh-21650