RFR: Update README.md to be used as Release Notes for Leyden EA 2 [v2]

[Dan Heidinga]

On Wed, 27 Aug 2025 17:26:39 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> In Leyden EA 1, we used a special version of README.md as the release nodes:
>> 
>> https://jdk.java.net/leyden/ -> [Release Notes](https://github.com/openjdk/leyden/blob/leyden-ea1-release-notes/README.md)
>> 
>> As we are releasing Leyden EA 2, we will use the same process for the release notes.
>> 
>> - The README.md is taken from the [GIT version of Leyden EA 2 candidate](https://github.com/openjdk/leyden/commit/ffacb36e564b24e335b11fe5be8e574dffac2055) (as of today).
>> - Removed information about building and benchmarks
>> - Removed mentions of AOT features that have already been integrated into the mainline.
>> - Updated the terminology from "CDS" to "AOT"
>> 
>> A rendered version of this document can be found here:
>> - https://github.com/iklam/leyden/blob/leyden-ea2-release-notes/README.md
>> 
>> (I will merge some of the above changes back to leyden/premain branch after this PR is integrated).
>
> Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Added info about CPU matches and diagnosing loading errors; fixed typos

Thanks Ioi for updating this!

-------------

Marked as reviewed by heidinga (Committer).

PR Review: https://git.openjdk.org/leyden/pull/92#pullrequestreview-3161346943