Per anti-patterns.md item #9, guild-related SQL was scattered across
~15 handler files with no repository abstraction. Following the same
pattern established by CharacterRepository, this centralizes all
guilds, guild_characters, and guild_applications table access into a
single GuildRepository (~30 methods).
guild_model.go and handlers_guild_member.go are trimmed to types and
pure business logic only. All handler files (guild_*, festa, mail,
house, mercenary, rengoku) now call s.server.guildRepo methods
instead of direct DB queries or methods on domain objects.
Add package-level documentation (doc.go) to all 22 first-party
packages and godoc comments to ~150 previously undocumented
exported symbols across common/, network/, and server/.
Add explicit error discards (_ =) for Close() calls on network
connections, SQL rows, and file handles across 28 files. Also add
.golangci.yml with standard linter defaults to match CI configuration.
