Unify NodeJS and browser implementation

[EzraBrooks]

Public API Changes

• Removal of raw TCP socket support and NodeJS-stream-based Topic API
• Removal of "RosLibNode" and "RosLibBrowser" in favor of a singular "RosLib" entrypoint.

Description

Removing this Node-specific functionality that seems to be largely untouched in almost 10 years allows having one unified entry point into the codebase. This decreases the maintenance burden of the library and opens the door to swapping these transports out at runtime instead of at build-time; with ESM and dynamic imports, that is very doable - but would require a lot of rearchitecture to accommodate a Promise-based async API for any functions that would use a dynamic import (since that returns a Promise)

[EzraBrooks]

This is yet another thing that has become a hurdle in #665, since import statements are evaluated at script load time, unlike require (which is just a function call).