Bring the two playground-only exploration UIs into manifold ahead of the
playground's retirement (one-core-engine refactor §P1):
- Jolt: press-and-hold continuous weight-morph, release to freeze.
- Explore: Ornstein-Uhlenbeck exploration intensity on the output vector.
Interim TS maths ported verbatim from the retired playground modules
(engine/jolt.ts, engine/ou-explore.ts). The ExplorationController
(engine/exploration.ts) is the single P3 swap boundary: it drives Jolt via the
existing EngineApi get/set-weights + process route, and OU via a new inert-by-
default output-morph hook on the spine. In §P3 only that module changes to call
nisps_ml_jolt_press/release + nisps_ml_explore_intensity.
UI lands in the Learning drawer (Jolt hold-button + Explore slider), monochrome-
consistent, British copy. Gates green: typecheck, build, Playwright smoke.
