fix: catch panics from EC point creation (e.g. the point is at infinity)

[just-mitch]

Description

Problem*

Presently noir programs panic when trying to add points not in the curve.

For example:

#[test]
fn test_addition_with_zero() {
    let a = pedersen_commitment([1]);
    let b = pedersen_commitment([0]); // returns the point at infinity
    let result = a + b; // panics

    let expected = pedersen_commitment([1]);
    assert(result == expected);
}

Summary*

Ideally we would check if one of the operands to the ec addition is the point at infinity and return the other operand if so. This at least prevents it from panicking and returns a nicer error.

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[github-actions]

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