Add persistent storage stats in status console

This allows to inspect the usage of the persistent partition, which is
otherwise not inspectable without remote access. Other partitions are
not included on the assumption that a reboot would fix everything due to
their volatile state of being.

application/playos-status.nix

@@ -11,6 +11,7 @@ let
         screen=$(xrandr --current | grep '*' | awk '{print $1}')
         networkCount=$(connmanctl services | grep wifi | wc -l)
         rfid=$(opensc-tool --list-readers | pr -T -o 2)
+        dataDiskFree=$(df -h /mnt/data | pr -T -o 2)
         controller=$(systemctl is-active playos-controller)
         time=$(date +'%T %Z')
         printf "\033c"
@@ -19,6 +20,8 @@ let
           "Wi-Fi networks found: $networkCount" \
           "RFID readers connected:" \
           "$rfid" \
+          "Persistent storage:" \
+          "$dataDiskFree" \
           "Controller: $controller" \
           "Updated at: $time" \
           > ${ttyPath}

controller/Changelog.md

@@ -6,6 +6,7 @@
 - os: Split system definition into base and application layers
 - os: Make build outputs and displayed system name configurable through application layer
 - os: Include live system ISO in deployed outputs
+- status screen: Display persistent storage usage statistics
 
 # [2023.2.0] - 2023-03-06