feat: add packaged console script entrypoint to support uvx execution

[wangauone]

This PR adds support for running evalbench globally using uvx evalbench from anywhere in the terminal.

What Changed

• Exposed CLI Command: Registered evalbench as a command-line script inside pyproject.toml.
• Created Entrypoint: Added a simple run() function in evalbench.py to boot up the program.
• Fixed Global Imports: Added a search-path map in __init__.py to make sure Python can find our internal files (like util and reporting) when the package is installed globally.

How to Test

uv build
uvx --from dist/evalbench-1.7.1-py3-none-any.whl evalbench --help

[wangauone]

/gcbrun

[IsmailMehdi]

/gcbrun