Fix version separator and update purl-spec

[maennchen]

Two independent changes, one commit each.

Split the version at the last @ instead of the first

The version is separated from the name by the last unencoded @, but binary:split/2 without global splits at the first one. Names that themselves contain an @ — such as the Homebrew formula node@20 — were parsed as name node with version 20@20.10.0 instead of name node@20 with version 20.10.0.

Update purl-spec to dd9ffe9 and regenerate type data

Adds the new brew and git types and picks up changes to 17 existing definitions, bringing the registry to 42 types.

The hex doctest is updated for the re-encoded repository_url example, and two groups of new spec tests are excluded:

• The git tests expect an unencoded / inside the name (e.g. forgejo/forgejo), but / is the namespace separator in the purl grammar, so it has to be encoded as %2F. One of those fixtures is also corrupt, expecting forgejoforgejo/ with the slash misplaced.
• The cpan rule that a distribution name must not contain :: only exists as prose in the name_definition note, not as a machine readable field such as permitted_characters, so it cannot be enforced from the type definition.