Second "#of beams" window for Storm Rain when used in dual setup (self-cast and with ballista totems)

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Is your feature request related to a problem?

When two separate Storm Rain setups are present in a build, only one "# of overlapping beams" window is available. This generates incorrect DPS values, as the two skills have different damage calculations based on different supports, but they both use the same window.

Describe the solution you'd like

Enable a second window for the number of beams when a skill setup with a ballista totem + storm rain is present alongside self-cast storm rain.

Describe alternatives you've considered

An alternative workaround could be for the single window to count overlapping beams of all Storm Rain instances at once, but I don't see how it would correctly calculate DPS for those said instances.

Additional context

Current PoB for reference: https://pastebin.com/bpCdMzBY

issue 中没有指定文件或测试。首先定位现有的 Storm Rain “# of overlapping beams”窗口，以及对 self-cast 和 ballista-totem 配置的处理；完成的标准是两种配置可以使用彼此独立的 beam 数量，并产生正确的 DPS 值。