Refactor (src/webserver.js): reduce complexity in listen() AND Document (src/webserver.js): Added comments, small formatting improvements

[yuriiShmal]

P1B: Starter Task: Refactoring PR

1. Issue

Link to the associated GitHub issue:
#117

Full path to the refactored file:
src/webserver.js

What do you think this file does?
This file defines how the web server for Nodebb on the machine that is it run on will be established. Of particular interest is the fact that it attempts to bind a socket on the machine to listen for requests.

What is the scope of your refactoring within that file?
Rewrote the listen function, added comment documentation and small formatting improvements (no functionality/logical changes) to the entire file. Not requested, but AI made it easy, and it will be hepfull to future maintainers.

Which Qlty‑reported issue did you address?
Cognitive Complexity 20 in listen()

2. Refactoring

How did the specific issue you chose impact the codebase’s maintainability?
It helped users better understand the code. When a function has a high cognitive complexity, it is hard to understand what exactly it does. If someone needs to make changes to listen, they will be able to more quickly understand exactly what each part of listen does, and where they should make their changes.

What changes did you make to resolve the issue?
Used helper functions to break down the functionality of listen. Also added documentation throughout the file. webserver.js is a critical file, so I figured that these comments would be helpful.

How do your changes improve maintainability? Did you consider alternatives?
They clearly break down the functionality of the listen function into more clearly understandable functions, which each have a clear task. The comments also guide the reader through the functionality.

3. Validation

How did you trigger the refactored code path from the UI?
It was triggered automatically on startup (as it pertains to the webserver code that is run every time ./nodebb start is run). You can see it when it starts up (the webpage is displayed). If it were to fail, the page would be empty except for a text error displayed without any formatting and the logs would print: GET error.

Attach a screenshot of the logs and UI demonstrating the trigger.

Note that as it was triggered automatically when ./nodebb start was called, I can only show

Attach a screenshot of qlty smells --no-snippets <full/path/to/file.js> showing fewer reported issues after the changes.