Slaps now apply additive spring impulses that stack, producing a
satisfying wobble-and-return (~1s). Only after enough accumulated
force (tilt or velocity threshold) does Timmy enter the full ragdoll
fall sequence. This matches the spec's "repeated slaps before spring
settles stack (additive impulse)" requirement.
- Tuned spring constants (stiffness=18, damping=4.5) for visible wobble
- SLAP_IMPULSE actually used now (was defined but unused)
- Pip gets mild startle on wobble, full scatter only on ragdoll
- Crystal flash + sound still fire on every hit
Fixes#43
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
