Creating new grid breaks if axes labels not provided

Description of Bug

If I use assign_metrics_to_grid to make a new grid, and I don't provide a list of axes labels, it will crash and give a misleading error message:

  File "/home/wk9874/Documents/simvue/python-api/simvue/run.py", line 1434, in assign_metric_to_grid
    self._error(f"Grid '{grid_name}' is not defined.")
  File "/home/wk9874/Documents/simvue/python-api/simvue/run.py", line 606, in _error
    raise SimvueRunError(message)
simvue.exception.SimvueRunError: Grid 'test_metric_2d' is not defined.

I dont think axes labels should be required, it should probably default to 'x' for 2D metrics of ['x', 'y'] for 3D metrics. Although if you would prefer to be explicit and require axes labels, it should provide a more informative message

Steps To Reproduce

Code to reproduce the behavior:

import simvue
import numpy

with simvue.Run() as run:
    run.init("test")
    run.assign_metric_to_grid(metric_name="test_metric_2d", axes_ticks=numpy.arange(100))
    for i in range(10):
        run.log_metrics({"test_metric_2d": numpy.random.rand(10)}, time=i, step=i)

Expected behavior

Should create a grid and log a metric

Actual Behaviour

Error thrown

Screenshots

If applicable, add screenshots to help explain your problem.

Setup

• OS: Ubuntu 22.04
• Python version 3.10

simvue/run.py の 1434 行目にある assign_metric_to_grid の周辺を調査し、その後、軸ラベルがない状態で numpy を使って再現を実行してください。意図された動作がデフォルト値でグリッドを作成することなのか、それともより明確な検証エラーを報告することなのかを確認し、結果の動作が期待されるグリッドおよびメトリクスのロギングフローと一致することを検証してください。