Faster initial load on the admin dashboard

The admin dashboard's first paint was slower than it should have been because the boot sequence was doing more work than it needed to before showing you anything.

We trimmed three independent slices of work out of the entry chunk:

• The auth initializer no longer blocks page rendering on a profile fetch — your session is rehydrated from local cache instantly and the profile call fires in the background. That alone shaves 200 to 500 milliseconds of blocking time off every load.
• Anonymous visitors no longer pay for a guaranteed-empty projects fetch on auth pages.
• Our error monitoring no longer ships its heaviest module on every page; it loads on first user interaction instead.

The stats dashboard also got a real skeleton state inside its chart placeholders, so the area no longer flashes a generic spinner between the server-rendered shell and the first chart paint.

If signing into the admin felt sluggish before, this release is the most noticeable speed win in months.