Add readCharacterInt/adjustCharacterInt helpers for single-column
integer operations on the characters table. Eliminates fmt.Sprintf
SQL construction in handlers_misc.go and replaces inline queries
across cafe, kouryou, and mercenary handlers.
Second round of protocol constant extraction: adds constants_time.go
(secsPerDay, secsPerWeek), constants_raviente.go (register IDs,
semaphore constants), and named constants across 14 handler files
replacing raw hex/numeric literals. Updates anti-patterns doc to
mark #4 (magic numbers) as substantially fixed.
handleMsgSysOperateRegister returned without sending an ACK when the
payload was empty, causing the client to softlock waiting for a response.
Send doAckBufSucceed with nil data on the early-return path to match
the success-path ACK type.
Also update tests to expect error returns instead of panics from
unimplemented Build/Parse stubs (matching prior panic→error refactor),
and mark resolved anti-patterns in docs.
Several handlers used packet fields as array indices or SQL column
names without bounds checking, allowing crafted packets to panic the
server or produce malformed SQL.
Panic fixes (high severity):
- handlers_mail: bounds check AccIndex against mailList length
- handlers_misc: validate ArmourID >= 10000 and MogType <= 4
- handlers_mercenary: check RawDataPayload length before slicing
- handlers_house: check RawDataPayload length in SaveDecoMyset
- handlers_register: guard empty RawDataPayload in OperateRegister
SQL column name fixes (medium severity):
- handlers_misc: early return on unknown PointType
- handlers_items: reject unknown StampType in weekly stamp handlers
- handlers_achievement: cap AchievementID at 32
- handlers_goocoo: skip goocoo.Index > 4
- handlers_house: cap BoxIndex for warehouse operations
- handlers_tower: fix MissionIndex=0 bypassing normalization guard
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/.
Re-enable the golangci-lint job in CI (disabled Oct 2025), update to
Go 1.25 and golangci-lint-action v7. Fix errcheck, gosimple S1009,
staticcheck SA4031 and SA2001 errors across 54 files. Remaining ~39
lint errors will be addressed in follow-up commits.