Update installation documentation in README

[GFJHogue]

As noted in #85 (comment), the current setup instructions in the README are outdated and incomplete.

Should specify supported platforms (Unix x64) and troubleshooting common issues.

[Ehsanstp]

Hi @GFJHogue. I'd like to work on improving the README to address the installation confusion. I'm thinking for the following updates:

1. Clarify supported OS - specify that the project requires 64-bit Unix systems, recommend windows users to run this via WSL2 (Ubuntu recommended) with docker WSL2 enabled.
2. Chainlit-based run method is no longer supported - so that should be removed
3. Document the use of pre-built docker image
   For troubleshooting issues, I propose including the guidance on issues raised in the discussion. Such as - docker build taking an unexpectedly long time and the difference between building locally or using pre-built docker. Let me know if there are other common issues that should be documented.

[GFJHogue]

you're welcome to open a pull request!

[NaDa0Amr]

@GFJHogue @adamjohnwright I'm a GSoC contributor and I'd like to work on this issue.
#124 I've updated the README to provide better support for Linux users and to address common environment setup issues Happy to adjust anything based on feedback!