Replace the mutable global `_config.ErupeConfig` with dependency
injection across 79 files. Config is now threaded through existing
paths: `ClientContext.RealClientMode` for packet encoding, `s.server.
erupeConfig` for channel handlers, and explicit parameters for utility
functions. This removes hidden coupling, enables test parallelism
without global save/restore, and prevents low-level packages from
reaching up to the config layer.
Key changes:
- Enrich ClientContext with RealClientMode for packet files
- Add mode parameter to CryptConn, mhfitem, mhfcourse functions
- Convert handlers_commands init() to lazy sync.Once initialization
- Delete global var, init(), and helper functions from config.go
- Update all tests to pass config explicitly
Import 18 network packet test files and 5 server infrastructure test
files, adapted for main branch APIs: fix config import alias (_config),
remove non-existent DevMode field, use global handlerTable instead of
per-server handlers map, and correct validateToken mock expectations
to include both token and tokenID arguments.
Adds go-sqlmock dependency for database mocking in signserver tests.
