fix: default presence widgets to top of dashboard on fresh install

[josephfusco]

Fixes the out-of-the-box install experience where the presence widgets appeared at the bottom of the dashboard column (closes #105).

[github-actions]

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[github-actions]

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Boots a fresh WordPress with this PR's presence-api build, seeds 5 demo users, and drops you on the dashboard.

_{Stress-test variant: 40 demo users · Built from 643247849919909f3808b78b9fb8f34918db128a. Auto-updates when you push.}

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