* Housekeeping lib_rss.php
`lib_rss.php` had become much too large, especially after https://github.com/FreshRSS/FreshRSS/pull/7924
Moved most functions to other places.
Mostly no change of code otherwise (see comments).
* Extension: composer run-script phpstan-third-party
1. `include`, `include_once`, `require` and `require_once` are expressions not functions, parentheses are not necessary.
2. to move up the directory tree, it's better to use the `dirname` function instead of relying on `/..`.
* CLI database backup and restore
Can also be used to migrate from one database to another (e.g. MySQL to PostgreSQL) or to ease upgrade to a major PostgreSQL version (e.g. 15 to 16).
* +x
* Fix some cases
* Update to docker-compose-v2
* More documentation
