v2023.6
prepare-root: Changes made to find_proc_cmdline_key
switchroot,generator: Only read /proc/cmdline once
prepare-root: If composefs is configured as "maybe" don't fail
Use /run/ostree-booted metadata for sysroot-ro state passing
src/generator: Move all logic into libostree-1.so
switchroot: Document a bit more, add demo shell implementation