fix: add numpy to eval globals in eval_linKK for numpy 2.x compatibility

[alexbatgithub]

numpy 2.x changed scalar repr (e.g. np.float64(0.001) instead of 0.001), causing NameError when eval_linKK evaluated the generated circuit string in worker processes. Adding 'np': np to the eval globals dict resolves this.

[alexbatgithub]

Tested with Python 3.14.5 and numpy version: 2.4.6
test.py or:

import multiprocessing
import numpy as np
from impedance.validation import linKK


def _worker(q):
    try:
        f = np.logspace(-1, 4, 20)
        Z = 0.01 / (1 + 1j * 2 * np.pi * f * 1e-3) + 0.005
        linKK(f, Z, c=0.85, max_M=8, fit_type="complex", add_cap=True)
        q.put(("OK", None))
    except Exception as e:
        q.put(("ERROR", f"{type(e).__name__}: {e}"))


if __name__ == "__main__":
    f = np.logspace(-1, 4, 20)
    Z = 0.01 / (1 + 1j * 2 * np.pi * f * 1e-3) + 0.005

    print("Single-process call: ", end="", flush=True)
    linKK(f, Z, c=0.85, max_M=8, fit_type="complex", add_cap=True)
    print("OK")

    print("Spawned-process call: ", end="", flush=True)
    ctx = multiprocessing.get_context("spawn")
    q = ctx.Queue()
    p = ctx.Process(target=_worker, args=(q,))
    p.start()
    p.join(timeout=30)
    if p.exitcode is None:
        p.terminate()
        print("TIMED OUT")
    else:
        status, msg = q.get()
        print("OK" if status == "OK" else f"FAILED — {msg}")