Decode the Hex registry protobuf format, filter releases by fetching
timestamps from the Hex HTTP API (hex.pm/api/packages/{name}), and
re-encode without the original signature.
The protobuf handling uses protowire for low-level encoding/decoding
of the Signed wrapper, Package, and Release messages. Timestamps come
from the inserted_at field in the JSON API response.
Since the proxy re-encodes the payload without the original signature,
users need to disable registry signature verification.
* Fix all golangci-lint issues across the codebase
Resolve 77 lint issues reported by golangci-lint with gocritic, gocognit,
gocyclo, maintidx, dupl, mnd, unparam, ireturn, goconst, and errcheck
enabled. Net reduction of ~175 lines through shared helpers and
deduplication.
* Suppress staticcheck SA1019 for intentional deprecated field usage
The Storage.Path field is deprecated but still read for backwards
compatibility with existing configs that haven't migrated to the URL field.
All handler metadata and proxy requests were using http.DefaultClient directly,
bypassing any timeout or transport configuration. Added an HTTPClient field to
the Proxy struct with a 30-second default timeout, and updated every handler
to use it for upstream HTTP requests.
