Implement placeholder %E in Systemd services

[DavidePrincipi]

Newer Rocky Linux and Debian releases ship a breaking change in the way Systemd expands the %S placeholder. This issue is described and solved with a symlink automatic creation in #8028.

In old Systemd versions (up to Rocky Linux 9.8 and Debian 12) %S and %E placeholders both expand to ~/.config. In recent releases RL 9.8, Debian 13 %S expands to .local/state, reflecting upstream changes.

NS8 Systemd units often use %S as symbolic reference to ~/.config.

Proposed solution

Replace %S with %E in Systemd service units, for all NS8 applications. This replacement is more robust than relying on a symlink created when the Systemd user session starts.

Alternative solutions

Do nothing and continue to rely on the symlink created by fix #8028.

Additional context

• Upstream patch https://git.rockylinux.org/staging/src-rhel/rpms/systemd/-/blob/c9s/SOURCES/1313-execute-add-support-for-XDG_STATE_HOME-for-placing-s.patch?ref_type=heads

See also

• Bug Systemd %S breaking changes in Rocky Linux 9.8 #8028
• Discussion https://mattermost.nethesis.it/nethesis/pl/jb7c1zs6atn5bjsswenua7hk6e
• Forum fix release announcement https://community.nethserver.org/t/ns8-core-3-19-1-released-required-compatibility-update-for-rocky-linux-and-almalinux-9-8/27773