Maven central recently sunset the OSSRH and is migrating to
https://central.sonatype.com/

This PR updates the link in `RELEASING.md` to point to that site
instead.

Almost all the code fixes are for the new
[EffectivelyPrivate](https://errorprone.info/bugpattern/EffectivelyPrivate)
check.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **Chores**
  * Updated Error Prone version to 2.41.0 across all environments.
* **Refactor**
* Improved internal code encapsulation by restricting visibility of
constructors, fields, and methods in multiple components without
affecting user-facing functionality.
* **Tests**
* Added test annotation to a suppression suggestion test method for
improved test execution.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Fixes #1238 

Before we were missing a fallback case; now we just use the type of the
expression computed by `javac` (to be improved in the future).

<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **Bug Fixes**
* Improved handling of nullable type variables in generic methods to
ensure correct type inference in assignment contexts.

* **Tests**
* Added a new test to verify correct behavior when assigning
non-nullable arrays to nullable array parameters in generic methods.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

…on CollectionUtils.IsNullOrEmpty, and a couple Amazon StringUtils methods (#1242)

## Summary
This PR extends DefaultLibraryModels to recognize additional null-check
helper methods from common libraries, ensuring NullAway treats them as
guarding against null values.

Added support for:
* org.apache.commons.collections.CollectionUtils.isEmpty(Collection)
* org.apache.commons.collections4.CollectionUtils.isEmpty(Collection<?>)
*
software.amazon.awssdk.utils.CollectionUtils.isNullOrEmpty(Collection<?>)


Each method is now mapped so that NullAway understands they perform null
checks on their first argument.

Added corresponding unit tests in FrameworkTests to validate behavior
for Apache Commons Collections, Apache Commons Collections4, and AWS
CollectionUtils.

Impact
With these changes, NullAway will correctly recognize these helper
methods as null guards, reducing false positives when developers use
them to validate collections or objects before dereferencing.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **New Features**
* Broadened null/empty-check recognition to cover additional common
collection and string utilities (Apache Commons, Commons Lang/3, AWS SDK
utils, Spark utils, Android TextUtils), improving null-safety analysis.

* **Tests**
* Added tests validating handling of null/empty guards using Apache
Commons Collections, Commons Collections4 and AWS SDK utils.

* **Chores**
  * Added AWS SDK utils as a test dependency.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Manu Sridharan <[email protected]>

This adds (Ignored) tests for the failures for nullable super
invocations described in gh-1246

As of JDK 21.0.8, the patch to properly expose type use annotations via
standard APIs has landed, [guarded behind the flag
`-XDaddTypeAnnotationsToSymbol=true`](openjdk/jdk21u@bb83d59).
This PR runs the relevant tests on JDK 21 by passing that flag where
needed. This means NullAway regression tests will fail on versions of
JDK 21 older than 21.0.8, but we can document that.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

- New Features
- Improved compatibility with newer JDKs (21+), enabling enhanced
type-annotation handling where available.
- Tests
- Expanded test coverage by removing version-based exclusions and adding
runtime guards for newer JDKs.
- Updated test setup to conditionally enable features on supported JDK
versions.
- Chores
- Simplified build configuration by eliminating Java-version-specific
test filtering.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->