systemd-stdio-bridge: add page (#11330)

* systemd-stdio-bridge: add page

---------

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
Co-authored-by: Sebastiaan Speck <12570668+sebastiaanspeck@users.noreply.github.com>

pages/linux/systemd-stdio-bridge.md

@@ -0,0 +1,21 @@
+# systemd-stdio-bridge
+
+> Implement a proxy between `stdin`/`stdout` and a D-Bus.
+> Note: It expects to receive an open connection via `stdin`/`stdout` when started, and will create a new connection to the specified bus.
+> More information: <https://www.freedesktop.org/software/systemd/man/latest/systemd-stdio-bridge.html>.
+
+- Forward `stdin`/`stdout` to the local system bus:
+
+`systemd-stdio-bridge`
+
+- Forward `stdin`/`stdout` to a specific user's D-Bus:
+
+`systemd-stdio-bridge --{{user}}`
+
+- Forward `stdin`/`stdout` to the local system bus within a specific container:
+
+`systemd-stdio-bridge --machine={{mycontainer}}`
+
+- Forward `stdin`/`stdout` to a custom D-Bus address:
+
+`systemd-stdio-bridge --bus-path=unix:path={{/custom/dbus/socket}}`