hakurei 0.4.1

Fixes:
- Strings larger than a page is rejected by package `container`.

Enhancements:
- Overlay mounts are now configured via fsconfig(2) in package
  `container`.

Internal:
- Checksum helper command in `cmd/mbf`.
- Pass preferred job count via `internal/pkg`.
- Optionally open cache in `cmd/mbf`.
- Artifact IR daemon in `cmd/mbf`.
- Ongoing cures now supports fine-grained cancellation in
  `internal/pkg`.
- LLVM toolchain is now built in a single artifact.
- Binary stage0 distribution is shrunk to less than half its former
  size.
- The stage0 toolchain is now functionally equivalent to all future
  stages and is able to cure artifacts without special cases.
- Package status dashboard upstreamed in `cmd/mbf`.
-----BEGIN SSH SIGNATURE-----
U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAg/+8EpV0uLIR+MAtm7kYw4ssYDi
TAEe6cY2wdrwBLU38AAAADZ2l0AAAAAAAAAAZzaGE1MTIAAABTAAAAC3NzaC1lZDI1NTE5
AAAAQCgJ39YQ69O4FBNEpmWu39ctsngGZRdasYRxggkkTsjZMmFD4hiKSqdYj8AqbInn6N
HeDFkv/1QVMlMyngNpzAU=
-----END SSH SIGNATURE-----