[DevTools] Split extension bundle to comply with Firefox upload process

[bvaughn]

Apparently the release of the new scheduling profiler pushed us over some limit the Firefox store implies on extension script size:

Specifically, our main.js file is too large:

Maybe we can adjust the WebPack configuration to split this script into multiple parts and import those parts at runtime to work around this limit.

[yashu2001]

Hey, I'm a first-time contributor, can I work on this?
If yeah could you give me sources to look into?

[bvaughn]

This issue is already assigned to @lunaruan.

[lunaruan]

Closed by #22102