Parallel plot: controlling angle and position behavior

Hi plotly team,

When the labelangle is below some threshold, the axis label gets centered automatically (like "choose_from(...)" on the figure below). Instead, we'd like to control this behavior with a parameter, so that long texts can fit the screen nicely, with a low angle and right alignment with the axis. WDYT?

Ideally, something like:

import plotly.graph_objects as go

go.Figure(
    go.Parcoords(
        dimensions=[
            {
                "label": "hello " * 5,
                "values": [1, 2, 4, 5],
            }
        ],
        labelangle=20,
        labelside="top",
        align_center=False, # <-- 
    )
)

See: https://github.com/skrub-data/skrub/issues/1367

从 go.Parcoords 入口点开始，检查 labelangle 和 labelside 的公开方式及处理方式。确定所请求的 align_center 行为应放在哪里，然后添加覆盖测试，证明低角度标签可以保留所请求的对齐方式，同时不破坏现有默认值。