feat: basic playback functionality

src/sh/tools.sh

@@ -21,3 +21,19 @@ else
   exit 1
 fi
 export JQ
+
+if command -v "mpv" >/dev/null; then
+  MPV="mpv"
+else
+  err "Did not find mpv."
+  exit 1
+fi
+export MPV
+
+if command -v "socat" >/dev/null; then
+  SOCAT="socat"
+else
+  err "Did not find socat."
+  exit 1
+fi
+export SOCAT