Zephyr v4.2.0-rc1

The first release candidate for Zephyr 4.2.0 has been tagged:
https://github.com/zephyrproject-rtos/zephyr/releases/tag/v4.2.0-rc1

The merge window for features and enhancements is now closed for this release,
and it will remain closed until 4.2.0 is released.

We are now in the stabilisation phase, and only bug-fix, documentation, and
stabilisation patches may be merged to the main branch. Additional features and
enhancements, including new hardware support for the 4.2.0 release requires
approval by the TSC.

You may continue to submit pull requests for new features to gather feedback
early or collaborate with others, but the release team would like to encourage
everyone to focus on testing, documentation improvements and fixing bugs.

We anticipate the coming weeks to be very busy reducing overall bug count.
Please give this RC a test drive and report any issues on supported platforms
(with a PR if possible).

Release milestone dates:
https://github.com/zephyrproject-rtos/zephyr/wiki/Release-Management

Release process:
https://docs.zephyrproject.org/latest/project/release_process.html

Dan and Dan, and the full Zephyr Release Team