Feat/strict mode

[hardbyte]

Introduces a new EvaluationMode enum that allows developers to control how CEL expressions handle type compatibility, providing flexibility between Python-friendly type coercion and strict CEL specification compliance.

🎯 Evaluation Modes

• EvaluationMode.PYTHON (default for Python API): Enables Python-friendly type promotions (e.g., int + float → float)
• EvaluationMode.STRICT (default for CLI): Enforces strict CEL type rules with no automatic coercion

API Changes

Python API:

 
from cel import evaluate, EvaluationMode

# Python-friendly (default)
result = evaluate("1 + 2.5")  # → 3.5

# Explicit modes
result = evaluate("1 + 2.5", mode=EvaluationMode.PYTHON)  # → 3.5
result = evaluate("1 + 2.5", mode="strict")  # → TypeError

CLI:

$ cel '1 + 2.5' --mode python  # → 3.5
$ cel '1 + 2.5' --mode strict  # → Error (default)