Adds a catch-all fallback to hostMapper.Lookup() that matches any
hostname when a '.' mapping exists. After the existing three-phase
matching (exact -> dot-prefix -> suffix walk) fails, the lookup now
checks for a standalone '.' entry as a final fallback.
This enables users to map all hostnames to a single IP (e.g., for SNI
proxy usage) with a simple configuration like 'hosts=.:<ip>'.
Fixesgo-gost/gost#228
- hosts/hosts.go: add package and symbol doc comments, fix missing
httpLoader.Close() in Close()
- hosts/plugin: add doc comments for HTTP and gRPC plugin types
- hop/hop.go: add doc comments, accumulate reload/parse errors via errors.Join
instead of silently discarding them
- hop/plugin/http.go: add doc comments and missing Close() method
- Add unit tests for hosts (580 lines) and hop (991 lines)