fix: replace debug fmt.Println with hlog in printNode

[lxcxjxhx]

Description

Replace debug fmt.Println/fmt.Printf calls in printNode() with hlog.SystemLogger().Debugf() to use the proper logging framework.

Problem

printNode() in engine.go uses fmt.Println and fmt.Printf for debug output, which writes directly to stdout instead of using Hertz's logging framework (hlog).

This causes:

• Debug output bypasses the logging system configuration
• Cannot control log level or output destination for these messages
• Inconsistent with the rest of the codebase which uses hlog.SystemLogger()

Fix

Replace fmt.Println/fmt.Printf calls with hlog.SystemLogger().Debugf().

Changes

• pkg/route/engine.go: Replace 3 fmt.Print* calls in printNode() with hlog.SystemLogger().Debugf()

Testing

• go build ./pkg/route/... pass
• go test ./pkg/route/... pass (1.7s)

Related

• Fixes fix: replace debug fmt.Println with hlog in printNode #1525