Fix a number of small, old issues

[bdeitte]

I still need to review this further, but this should fix:
#119 (will require a major version bump)
#92
#198
#218
#120

[Copilot]

Pull request overview

This PR addresses multiple historical issues by improving mock mode behavior, optimizing DNS lookups for IP addresses, fixing event prefix/suffix handling, enhancing Telegraf tag sanitization, and ensuring safe socket cleanup.

Key Changes:

• Mock mode now creates a mock transport instead of real sockets
• IP addresses bypass DNS lookup to avoid APM instrumentation overhead
• Event titles now respect global prefix and suffix configuration
• Telegraf tags ending with backslashes are properly sanitized
• Socket error handler removal checks for socket existence

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
lib/transport.js	Implements mock transport, adds IP detection to bypass DNS lookups, assigns transport types before protocol-specific creation
lib/statsd.js	Guards socket.removeListener calls with socket existence checks, passes mock flag to transport creation
lib/statsFunctions.js	Applies prefix/suffix to event titles consistently with check() behavior
lib/helpers.js	Sanitizes trailing backslashes in Telegraf tags to prevent line protocol breaking
test/udpSocketOptions.js	Adds test coverage for IP address DNS lookup bypass behavior
test/init.js	Verifies mock transport creation and properties
test/helpers.js	Tests trailing backslash sanitization in various scenarios
test/event.js	Validates event title prefix/suffix application
test/close.js	Tests safe close behavior when socket is null
README.md	Updates mock mode documentation and reorders feature list
CHANGES.md	Documents all fixes in the changelog
CLAUDE.md	Notes debug logging capability

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[Copilot]

The callback is invoked without checking if it exists, but earlier in this code path (lines 111-112) it's conditionally invoked. This could cause an error if callback is undefined when a socketError occurs.