Extract `DefaultPropertiesPropertySource` from `SpringApplication` so
that logic can be easily accessed by other classes. Specifically the
property source name and logic to move the source to the end of the
list needs to be called from several places.

Closes gh-22520

Add a new `DeferredLogFactory` interface and `DeferredLogs`
implementation that can be used when a `DeferredLog` instance is needed
but the `switchOver` method should be handled elsewhere.

This interface has primarily been added so `EnvironmentPostProcessor`
classes will no longer need to implement `ApplicationEventListener`
just to switch over their logs.

Closes gh-22496

Update `OriginTrackedPropertiesLoader` so that it can support
multi-document properties files. These are similar to multi-document
YAML files but use `#---` as the separator.

Closes gh-22495
Co-authored-by: Phillip Webb <pwebb@vmware.com>

Add a factory method to `ConfigurationPropertySource` that allows a
single Spring `PropertySource` instance to be adapted.

Closes gh-22494

Update `OriginTrackedYamlLoader` so that empty documents are filtered
from the result. Prior to this commit, our origin wrapper would confuse
the YAML processor and cause empty documents to be included in the Map
with a key of "document" and no value.

Closes gh-22493

Update `OriginTrackedPropertiesLoaderTests` to also test that an escape
character can be the last character on a line.

Update value object binder support so that parameters can be annotated
with `@Name` if a specific property name should be used. Prior to this
commit is was not possible to use Java reserved words as property names.

Closes gh-22492

Closes gh-22389

Closes gh-22511

Closes gh-22385

Closes gh-22390

Closes gh-22386

Closes gh-22387

Closes gh-22383

Closes gh-22507

See gh-22505

Closes gh-22388

Closes gh-22384