Fix: bootstrap & CLI entrypoint; add __main__ for python -m jarviscli

[lrsierra]

Summary

Make python -m jarviscli work out of the box by adding a proper package entrypoint. Also add a small bootstrap test to guard this behavior going forward.

What Changed

• Added jarviscli/__main__.py so python -m jarviscli starts Jarvis by calling Jarvis().start() and then entering the command loop.
• Added tests: jarviscli/tests/test_bootstrap_entrypoint.py verifies the module exposes a main() and that calling it triggers Jarvis.start() (mocked).

No functional changes to plugins; this only addresses startup/bootstrapping.

Why

On a fresh clone, python -m jarviscli fails because the package has no __main__.py. Providing a standard entrypoint matches the README’s “Run Jarvis from anywhere,” reduces confusion for new contributors, and aligns with Python packaging conventions.

How to Test

From repo root:

# fresh venv (optional but recommended)
python3 -m venv .venv && source .venv/bin/activate
python installer

# ensure the repo is importable during dev
export PYTHONPATH="$PWD/jarviscli:$PWD:$PYTHONPATH"

# 1) Verify module entrypoint launches the app
python -m jarviscli   # should show the interactive prompt (type 'help' to confirm)

# 2) Run the new bootstrap test
python -m unittest jarviscli.tests.test_bootstrap_entrypoint -v