Review polish on the prior commit (30874c6):
- BuildDefaultViewer extract dropped the "filter out Id=0 placeholders
and dedupe" comment from the leader-skin grant block — restored.
- LinkSteamToViewer test now calls link twice and asserts count stays
at 1, exercising the alreadyLinked short-circuit.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Extracts the default-loadout body into a private BuildDefaultViewer
helper shared by the existing Steam-import path and a new
RegisterAnonymousViewer for /tool/signup. LinkSteamToViewer is the
seam SteamSessionAuthenticationHandler will call on first-Steam-touch
of a UDID-keyed viewer.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
