Feat/advanced area cli

[saqibmanan]

What

Adds a non-breaking, faster triangle area tool:

• advanced_area.py (interactive, CLI, batch; auto-NumPy for big inputs)
• area.md usage docs
• tests/test_advanced_area.py (pytest)

Why

• Keep area.py intact for beginners/tutorials.
• Provide CLI & batch support for scripting, CI, and large inputs.
• Optional NumPy acceleration for high throughput.

How to use

• Interactive: python advanced_area.py
• CLI: python advanced_area.py <base> <height>
• Batch: printf "3 4\n5 2\n" | python advanced_area.py
• Tests: pytest -q

Notes

• No changes to area.py.
• Works without NumPy; speeds up if NumPy is present.