Evict cached results to keep .barca/ under its size limit

Usage: barca gc [OPTIONS]

Options:
      --max-size <SIZE>
          A limit for this run in place of the configured one: 20GB, 500MB, 20GiB, bytes, 10% (of the filesystem) or off (only leftovers and superseded results)

      --dry-run
          Preview cached and planned work; execute nothing and record no run

      --json
          Emit JSON on stdout (the default when stdout is not a terminal)

      --pretty
          Emit human-readable output (the default when stdout is a terminal)

      --env <ENV>
          Use a separate cache and history for this environment

  -h, --help
          Show concise command help

      --examples
          Show all command examples without running anything

Examples:
  barca gc --dry-run              # what would be evicted, per tier, and what it leaves
  barca gc                        # evict now, down to 80% of [cache] max_size
  barca gc --max-size 5GB         # a one-off tighter budget
  barca gc --max-size off         # only leftovers and superseded results, all of them
  barca gc --json                 # {size_bytes, limit_bytes, after_bytes, tiers, evicted, ...}
  barca gc --env dev              # only the dev environment's results (leftovers are shared)

More: barca docs cache ("Disk use")
