- limiterGroup.Allow(): return false immediately on first denial instead of
continuing through all limiters (wasting tokens on subsequent limiters).
Sort limiters by Limit() so most restrictive fires first.
- rateLimiter.Close(): add missing httpLoader.Close() to prevent resource leak.
- Add doc comments for all exported symbols (package, constants, Options,
NewRateLimiter, NewLimiter, ErrRateLimit, generators).
- Add rate_test.go with 59 unit tests covering generators, limiter groups,
parsing (limit/line/patterns), reload, loader merge, Close behavior,
and priority ordering (exact IP > CIDR > $$ > $).
Add package and exported symbol doc comments across conn, generator,
limiter, and wrapper packages. Fix nil receiver guard in
connLimitSingleGenerator.Limiter, add missing httpLoader.Close call,
return context.Background instead of nil in serverConn.Context, return
explicit error on connection limit exceeded, and simplify Allow logic.
ginuerzh