feat (code-style): [website] libs, formatting, and conventions

[ferantivero]

Purpose

We wanted to provide a freshness update and cleanup over the code checking libs and refactoring the codebase to remove warnings

Does this introduce a breaking change?

[ ] Yes [x] No 

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix [x] Feature [x] Code style update (formatting, local variables) [x] Refactoring (no functional changes, no api changes) [ ] Documentation content changes [ ] Other... Please describe: 

How to Test

1. Start Devcontainer
2. Modify the appsettings.json with a valid ai endpoint address
3. Send a prompt
4. The bot should respond with a message

• Test the code

This PR is intentionally not introducing any unit tests

What to Check

Verify that the following are valid

• you can now easily spin-up a devcontainer to run the website
• remove dead code
• follow principal .NET conventions
• implement domain naming conventions
• removed all warnings
• libs are up to date
• vanilla js and simplified markup
• the zip is updated

Other Information

Working with mocked endpoint

Err handling (the website couldn't reach out the ai endpoint)

[ckittel]

Besides removing "GPT" here are some other items for you to review/consider. But generally speaking, this looks great.