* typo in phpdoc
* add first draft for adding replies collections to posts and comments
* refactoring
* Fix php CodeSniffer violations
* fix typo in php comment
* add draft for testing replies
* replies: test with own comment
* fix basic test for replies collection
* Restrict 'type' parameter for replies to 'post' or 'comment' in REST API
* some cleanups
* prefer ID over URL
* rename to `reply_id` to make clear that it is not the WordPress comment_id
* modularize retrieving of comment link via comment meta
* fix phpcs
* I think we should be more precise with this
and maybe there are other fallbacks coming
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Co-authored-by: Matthias Pfefferle <pfefferle@users.noreply.github.com>