audio-bridge: custom pipewire-pulse.conf with TCP 4713 listener

Alpine's pipewire-pulse binary is stripped (-a option removed); the
only way to configure listening address is via config file. Add
/etc/pipewire/pipewire-pulse.conf that overrides server.address to
include tcp:4713 alongside the default unix:native socket.

Server addresses now:
- unix:native (for in-container clients)
- tcp:4713 (for sibling containers connecting via PULSE_SERVER env var)

infra/audio-bridge/Dockerfile

@@ -19,6 +19,7 @@ RUN apk add --no-cache \
 
 COPY entrypoint.sh /entrypoint.sh
 RUN chmod +x /entrypoint.sh
+COPY pipewire-pulse.conf /etc/pipewire/pipewire-pulse.conf
 
 # D-Bus socket dir for bluetoothd / wireplumber / pipewire
 VOLUME ["/run/dbus", "/run/user/0"]

infra/audio-bridge/entrypoint.sh

@@ -38,8 +38,8 @@ sleep 1
 # PipeWire (audio server). Listens on its own native socket.
 pipewire &
 
-# PipeWire-Pulse daemon: PA-compatible bridge. Listen on TCP 4713 so PA clients
-# (librespot, mopidy) can connect from sibling containers without unix socket
-# path coupling.
+# PipeWire-Pulse daemon: PA-compatible bridge. Custom config in
+# /etc/pipewire/pipewire-pulse.conf sets server.address = [unix:native, tcp:4713]
+# so PA clients (librespot, mopidy) connect via tcp:127.0.0.1:4713.
 sleep 1
-exec pipewire-pulse -a tcp:4713 -a unix:/tmp/pulse-socket
+exec pipewire-pulse

infra/audio-bridge/pipewire-pulse.conf

@@ -0,0 +1,12 @@
+# Custom PipeWire-Pulse config: override server.address to add TCP 4713 listener.
+# This file is loaded from /etc/pipewire/pipewire-pulse.conf and overrides
+# defaults from /usr/share/pipewire/pipewire-pulse.conf.
+#
+# PA clients (librespot, mopidy) connect via tcp:127.0.0.1:4713.
+
+pulse.properties = {
+    server.address = [
+        "unix:native"
+        "tcp:4713"
+    ]
+}