Ports the prototype's economy verbatim: $80 budget, $5/$15/$30 hardware
tiers, $15 spare, tension 0.6-1.4. Adds unrig-with-refund, which the
prototype lacked — a misclick there was unrecoverable, and a full refund
costs the economy nothing.
RiggingSession holds all the rules and is three-free and DOM-free, so it
tests headless. The picking UI is left as an explicit seam: it needs Lane
A's camera and anchor markers to raycast against, which do not exist yet.
One assert encodes a design invariant rather than a code fact: $80 must
not buy rated shackles on all four corners. DESIGN.md's economic tension
is that you always field one dodgy corner and choose which one; if that
test ever passes, the budget has become decoration.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>