feat: make extension browser-compatible

[SunsetTechuila]

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fixes #327

[SunsetTechuila]

nah, i'm done

here is the attempt to adapt tests for web version: SunsetTechuila@0265a95

also finishing this will require to make the editorconfig package use workspace.fs instead of fs. this can be done with https://github.com/thlorenz/proxyquire or patching