Solver-agnostic ray/line picking on the physicsData seam

[krisnye]

Description

Adds a pluggable, solver-agnostic spatial-query seam for picking on
@adobe/data-gpu/physics, fulfilled interchangeably by both reference solvers.

• physicsQuery resource + pickRay / pickRayEach actions on the
  physicsData seam. The active solver publishes its engine-backed
  implementation once its WASM world is live; consumers pick without knowing
  which solver is running.
• With or without radius — a thin ray, or a sphere of radius swept along
  the segment, behind one option.
• pickRay returns the nearest collider as a fresh, retainable PhysicsHit
  (entity, parametric α ∈ [0,1] matching graphics PickHit, world point,
  ray-opposing normal).
• pickRayEach visits every collider along the segment, nearest first, with
  early-out, passing a single reused (zero-allocation) hit.
• Backed by each engine's native cast — Rapier castRayAndGetNormal /
  castShape / intersectionsWithRay; Jolt NarrowPhaseQuery.CastRay /
  CastShape with all-hit collectors. Entity resolved via body userData.

Radius all-hits is native on Jolt; the Rapier compat binding has no swept-shape
all-hits query, so a radius pickRayEach degrades to the nearest hit there
(documented on the interface). Graphics picking (renderable-Model AABB) is
left untouched — physics picking is collider-based and separate.

Testing

• Abstract conformance suite (pick-ray-conformance.test.ts) run against both
  solvers: entity/α/point/normal, nearest-of-several, clean miss, with/without
  radius, all-hits ordering + early-out, and the zero-alloc scratch-reuse vs.
  fresh-castRay contract.
• Unit test for the shared orientNormalAgainstRay helper.
• Full physics suite passes (39 tests); monorepo lint + typecheck clean.

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