330 non-vendor files had minor formatting inconsistencies (comment alignment, whitespace). No logic changes.
The config package used `package _config` with a leading underscore, which is unconventional in Go. Rename to `package config` (matching the directory name) and use `cfg` as the standard import alias across all 93 importing files.
Add unit tests across multiple packages: - byteframe: SetBE/SetLE byte order switching - config: Mode.String() for all safe version ranges - mhfpacket: 28 Parse methods, 5 Build methods, empty packet builds, variable-length packets, NOT IMPLEMENTED error paths, UpdateWarehouse - network: PacketID.String() for known IDs, out-of-range, and all valid - channelserver: handleMsgMhfGetPaperData (6 switch cases), grpToGR (11 input values), gacha handlers, TimeGameAbsolute, equipSkinHistSize (4 config branches), guild mission handlers, dumpSaveData disabled path - entranceserver: makeHeader with various inputs