* systemd: Use network-online.target for server
Fixes#2186
ss-server needs to wait for the network to be up to be able to bind to non-wildcard IPs. Interface is configured at `network-online.target` but not at `network.target`.
ss-local unit is kept the same, with `After=network.target` for proper ordering at shutdown - unit is stopped before network is shutdown.
* systemd unit: improvements
`exec` is [recommended](https://www.freedesktop.org/software/systemd/man/latest/systemd.service.html#Type=).
Add `NoNewPriviledges` which has been used in [Arch packaging](https://gitlab.archlinux.org/archlinux/packaging/packages/shadowsocks-rust/-/blob/main/shadowsocks-rust-server%40.service?ref_type=heads).
Add `CAP_NET_ADMIN` in ss-local which is needed for TUN mode.
Removed `CAP_NET_BIND_SERVICE` from ss-local. Do you really need to bind to priviledged port in *client*?
Debian unit left un-hardened. I'm not sure why it's different from the other ss-server unit.
* debian: fix up postinst bad substitution
Fix up postinst bad substitution caused by Bash string manipulation in the Dash script.
* debian: update compat file
Fix up the warning caused by compatibility levels before 10 are deprecated.
* debian: replace user nobody in systemd file with dynamicuser
* debian: remove dependency on apg and pwgen in control file
* debian: update shadowsocks-rust-server@.service
Add `DynamicUser=yes` in shadowsocks-rust-server@.service
* debian: update shadowsocks-rust-local@.service
Add `DynamicUser=yes` in shadowsocks-rust-local@.service
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Co-authored-by: mesher2024 <mesher2024@users.noreply.github.com>
Klaaktu
mesher2024andmesher2024
wevsty
Simon Shi