Packaging: the binary and package are inbuxa, INBUXA_* settings with STALWART_* fallback

- crates/main: package and [[bin]] renamed to inbuxa; homepage inbuxa.org;
  license AGPL-3.0-only (upstream is dual; the fork takes the AGPL).
- types::branding::env_var reads INBUXA_<name>, falling back to
  STALWART_<name> with a warning, for all nine server settings.
  STALWART_APP_ and STALWART_SPAM_* storage keys are unchanged.
- New-install default paths /var/lib/inbuxa and /var/log/inbuxa.
- Dockerfiles, systemd unit, launchd plist and AppArmor profile renamed.
- Upstream's .github moved to .github-upstream so none of it runs.
- install.sh stubbed: upstream's would install Stalwart.
- Two missed brand strings: the SMTP Received header and the utils user agent.

resources/systemd/inbuxa.mail.plist

@@ -4,12 +4,12 @@
 <plist version="1.0">
     <dict>
         <key>Label</key>
-        <string>stalwart.mail</string>
+        <string>inbuxa.mail</string>
         <key>ServiceDescription</key>
-        <string>Stalwart</string>
+        <string>INBUXA</string>
         <key>ProgramArguments</key>
         <array>
-            <string>__PATH__/bin/stalwart</string>
+            <string>__PATH__/bin/inbuxa</string>
             <string>--config=__PATH__/etc/config.json</string>
         </array>
         <key>RunAtLoad</key>

resources/systemd/inbuxa.service

@@ -1,5 +1,5 @@
 [Unit]
-Description=Stalwart Server
+Description=INBUXA Server
 Conflicts=postfix.service sendmail.service exim4.service
 ConditionPathExists=__PATH__/etc/config.json
 After=network-online.target
@@ -11,10 +11,10 @@ KillMode=process
 KillSignal=SIGINT
 Restart=on-failure
 RestartSec=5
-ExecStart=__PATH__/bin/stalwart --config=__PATH__/etc/config.json
-SyslogIdentifier=stalwart
-User=stalwart
-Group=stalwart
+ExecStart=__PATH__/bin/inbuxa --config=__PATH__/etc/config.json
+SyslogIdentifier=inbuxa
+User=inbuxa
+Group=inbuxa
 AmbientCapabilities=CAP_NET_BIND_SERVICE
 
 [Install]