Improvement/correct timestamps

[jafayer]

See #25

This pull request introduces several enhancements and refactorings to improve the event handling system and network request processing. The key changes include the creation of a TypedEventEmitter class, updates to network handler interfaces, and the addition of request timing metadata.

Event Handling Improvements:

• src/common/core/events.ts: Introduced TypedEventEmitter class to provide type-safe event handling.
• src/types/server.ts: Updated DNSResponse to extend TypedEventEmitter and added DNSResponseEvents interface for type-safe events. [1] [2] [3]

Network Handler Refactoring:

• src/common/network/net.ts: Updated NetworkHandler interface to accept a DNSRequest object instead of individual parameters. [1] [2]
• src/common/network/http.ts: Modified DNSOverHTTP to use the updated NetworkHandler interface and added request timing metadata. [1] [2] [3]
• src/common/network/tcp.ts: Updated DNSOverTCP to use the new NetworkHandler interface and added request timing metadata. [1] [2] [3]
• src/common/network/udp.ts: Adjusted DNSOverUDP to utilize the updated NetworkHandler interface and included request timing metadata. [1] [2] [3]

Example Update:

• src/examples/helloWorld/index.ts: Added DNSOverHTTP examples to the helloWorld example setup. [1] [2]

[jafayer]

Just a note that at some point the future we should probably find a way to do this more cleanly. Currently we're instantiating "request" timestamps when the Request object is created, then overriding them with the actual values that translate to the pre-data-event timestamps, representing network latency and deserialization. We may want to just allow the user to pass in timestamps to the request object?