Improve the configuration for Composer package (#100)

Co-authored-by: gziolo <gziolo@git.wordpress.org>
Co-authored-by: emdashcodes <emdashcodes@git.wordpress.org>
Co-authored-by: budzanowski <budzanowski@git.wordpress.org>

Fix REST API initialization for composer package usage (#55)

* Fix REST API initialization for composer package usage

- Move REST API route registration from abilities-api.php to bootstrap.php
- Ensure REST API routes are initialized when used as composer package
- Prevent duplicate registration by placing hook inside class existence check
- Consolidate initialization logic in single location

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Co-Authored-By: Claude <noreply@anthropic.com>

* Remove trailing whitespace

* Use tabs for indent.

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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Greg Ziółkowski <grzegorz@gziolo.pl>

Co-authored-by: budzanowski <budzanowski@git.wordpress.org>
Co-authored-by: gziolo <gziolo@git.wordpress.org>
Co-authored-by: justlevine <justlevine@git.wordpress.org>

docs: add installation steps for release (#48)