// Package config defines the ExploreDNS runtime configuration, flag parsing
// helpers, input validation, and usage text.
//
// Config holds all settings that control traversal behaviour and output.
// DefaultConfig returns a ready-to-use Config with sensible defaults.
// After populating Config from CLI flags, call Validate to ensure
// all field values are within their accepted ranges.
//
// Helper functions such as ParseQueryType, ParseDebugLevel, and
// ParseRootServer are pure converters; they never read flag state.
package config