Use new deb822 sources format in apt setup instructions

What happened?

Hi everyone, first of all, thank you for this wonderful product that is Syncthing 🙂

I am running Debian testing "forky" and upon running sudo apt update it was warning me that the PGP key for Syncthing would expire in 1 year. So I thought that maybe my install was obsolete and I decided to update Syncthing properly, following your instructions in https://apt.syncthing.net/ .

Upon trying, it seems like these instructions were obsolete as I saw many differences with my Debian system.

1 - Location of PGP keys

The guide says that keyrings should be stored in : /etc/apt/keyrings/

But from what I see on my system they should be stored in : /usr/share/keyrings

2 - Format of the files inside /etc/apt/sources.list.d/

The guide creates the file /etc/apt/sources.list.d/syncthing.list, and that works, sudo apt update shows no errors. ✔️

However, is the format .list going to be deprecated soon ? Because a file named syncthing.sources was already in this folder and this is its contents :

Types: deb
URIs: https://apt.syncthing.net/
Suites: syncthing
Components: stable
Signed-By: /usr/share/keyrings/syncthing-archive-keyring.gpg

I assume that Debian automatically transformed the previous .list file into this new .sources file when I last upgraded my system. Strange stuff 🤷‍♂️

Thank you for reading me.

Any questions or anything you want me to test, don't hesitate to ask. Thanks 👋

Syncthing version

v1.30.0

Platform & operating system

Linux (64-bit Intel/AMD) - Debian Testing "forky"

Browser version

No response

Relevant log output

Start with the installation instructions at apt.syncthing.net and compare their keyring location and syncthing.list guidance with the reported syncthing.sources content. Update the instructions to reflect the current Debian setup, then verify that the documented commands and paths match the expected apt configuration.