rustPlatform.fetchCargoVendor doesn't support v1 lockfile format

[TomaSajt]

fetchCargoVendor doesn't support lockfile format v1 yet
Note: importCargoLock supports lockfile format v1

• lockfile v1 doesn't have the checksums inside of the main package array.
• but instead under the metadata."checksum {name} {version} ({source})"
• packages that still have an old lockfile:
  • lipl
  • kubernix
  • system-syzygy

---

Here's how a v1 lockfile's metadata field looks like

[metadata]
"checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
"checksum atty 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)" = "1803c647a3ec87095e7ae7acfca019e98de5ec9a7d01343f611cf3152ed71a90"

---

Here are the logs if we try to use fetchCargoVendor on a v1 lockfile:

"""
Traceback (most recent call last):
  File "/nix/store/f2krmq3iv5nibcvn4rw7nrnrciqprdkh-python3-3.12.9/lib/python3.12/multiprocessing/pool.py", line 125, in worker
    result = (True, func(*args, **kwds))
                    ^^^^^^^^^^^^^^^^^^^
  File "/nix/store/f2krmq3iv5nibcvn4rw7nrnrciqprdkh-python3-3.12.9/lib/python3.12/multiprocessing/pool.py", line 51, in starmapstar
    return list(itertools.starmap(args[0], args[1]))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/h536wymibaydldashx6s1ccpw9cbyb75-fetch-cargo-vendor-util/bin/fetch-cargo-vendor-util", line 80, in download_tarball
    expected_checksum = pkg["checksum"]
                        ~~~^^^^^^^^^^^^
KeyError: 'checksum'
"""