Auto expand file system on first boot

[zehnm]

Expected Behavior or Design

When using a SD card which is larger than the remote-os (> 1 GB), the root partition should auto-expand to use available space. Otherwise the root partition remains at ~ 500 MB.

Current Behavior or Design

Partition remain the same as defined in the SD card image.

Possible Solution

At first boot auto-expand the root partition. Maybe add a marker file / configuration option in the /boot partition to enable / disable auto-expansion.

Detailed Description and Additional Information

For a possible solution to imitate how Raspian expands the file system: https://www.raspberrypi.org/forums/viewtopic.php?t=174434#p1113971

[zehnm]

In remote-os release v2 this issue relates to the ext4 data partition, which is kept to ~100MB in the default image.
On first boot the partition should be extended.