Also: move descriptions about difference between the playbook tags (setup-all and install-all) and about the just "recipe" from installing.md to maintenance-upgrading-services.md
Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>
* rewrite `just update` command to provide a one-line command to update everything
* update prefix
* uncomment update-self
* Revert requirements.yml updates not belonging to this PR
* Justfile and documentation updates to make things clearer
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Co-authored-by: Slavi Pantaleev <slavi@devture.com>