0.5.1

⚠️ Breaking — renamed public methods (on* → add*Listener / handle*)

No peer-dependency changes this release. The break is a method rename: tosijs's elementCreator treats any on<Event>-named member as addEventListener sugar and shadows a component method of the same name (it now fires a live warning, and it was a latent bug — the handler silently never ran). So the multi-listener subscribe methods and the lifecycle hooks moved off the on* prefix. The new names are also more honest: the subscribe methods push to a listener list (add/remove semantics), not a single-handler setter.

What a consumer must do: if you wrote a custom scene child that called owner.onSceneAddition(cb) / owner.onOriginShift(cb), or subclassed B3dControllable and overrode onGainFocus/onLoseFocus, or a gamepad source with an onButton callback, rename to the new members. It's a pure rename — signatures are unchanged. Built-in components are all migrated; this only affects code you wrote against these surfaces.

Added

• Coordinate-free MinSimApi (world-contract.ts §8) — a world-simulation boundary where coordinates never cross the membrane: a driver (an AI narrative engine, a scripted demo) sees topology + a qualitative distance ladder, never x/y/z. Places, portals, a 7-rung proximity ladder (same-spot…present, elsewhere for a different place), a SchematicView ("where am I", exits, contents-with-rung), and route(). WorldStore now implements it alongside its existing surface — the sim keeps real geometry sim-private and answers only in qualities.
• world-topology.ts — the pure, Babylon-free, deterministic spatial math behind the surface: proximityRung(distance, extent) (a distance in, an adjective out; bands scale with a place's extent), rungNominal (the inverse, for placement), routePortals (cheapest portal path, bidirectional, locked portals impassable — Dijkstra, deterministic tie-break), containmentPath (root→here breadcrumb). Unit-tested without a store or an engine.
• min-sim-conformance.ts — a framework-agnostic shared conformance kit (runMinSimConformance(makeApi, harness)) that pins the contract behaviour identically for any MinSimApi implementation. It imports no test runner (so it ships in the library) and takes the describe/test/expect harness as an argument — the same kit runs in this repo and in a driver's repo (the Ariosto use case), proving both stores behave the same at the seam.
• Clouds drift with wind — the cloud layer now moves with the wind vector, so the sky is alive rather than a still image.

Changed

• Demo cameras migrated to a shared demo-utils orbitCam helper (tilt-clamped so an orbit can't dip below the horizon) instead of 24 hand-rolled per-demo cameras. Authoring-only — no library-API impact.

Fixed

• Cloud whiteout now behaves correctly: it ramps to full earlier (less "snaps on at the moment of entry", denser once inside), blots out the sky (not just scene geometry), and mutes projected cloud shadows under the whiteout (fogged fragments no longer darken through the fog).
• b3d-controller player now defaults to false. tosijs began throwing on an initAttributes boolean that defaults to true (an absent HTML boolean attribute is false, so a true default can never turn on) — the old player: true default made the controller throw at construction and silently never wire input.