feat: WASM bridge rendering the WorldGraph twin over SuperSplat

[ruvnet]

Summary

End-to-end, no-backend integration that renders the privacy-aware WorldGraph
semantic twin over a SuperSplat
(PlayCanvas / WebGPU) Gaussian splat in the browser, via WebAssembly.

The headline detail: the original integration sketch used field names that do
not exist in this codebase (node.type, ZoneBoundsEnu, {east,north,up},
from_json(&str)). This PR is built against the real serde wire format
(node.kind, node.bounds_enu shape-union, EnuPoint{east_m,north_m,up_m},
from_json(&[u8])) — and native tests pin that contract so it can't silently
drift. See the mapping table in ADR-200.

What's here

worldgraph-wasm/ — Rust → WASM bridge (cdylib + rlib)

• bridge.rs — wasm32-only #[wasm_bindgen] surface; a thin
  serde-wasm-bindgen serializer (uses json_compatible() so ids cross as JS
  number, not BigInt).
• core.rs / enu.rs / overlay.rs — pure, host-tested logic: physical-node
  filtering, render-primitive geometry, ENU⇄PlayCanvas mapping, click-to-audit
  provenance cards, OccWorld trajectory overlays, and the configurator's
  PlayCanvas→ENU projection.
• build-wasm.sh — wasm-pack build helper.

supersplat-bridge/ — TypeScript / PlayCanvas integration

• types.ts — the serde wire format, exactly.
• SemanticVisualizer — typed wrapper; the WASM module is injected, so it
  unit-tests headlessly against an in-memory fake.
• WorldgraphScene reconciler (create / update-in-place / destroy) +
  PlayCanvasBackend.
• Four spatial apps: zero-video control room, visual configurator,
  OccWorld predictive debugger, click-to-audit provenance.

docs/adr/ADR-200..203 + INTEGRATION.md — architecture, the
ENU coordinate contract, the four applications, and the verification-driven
("Darwin") evolution loop with the generations actually run.

Testing

Both suites are green and require no browser and no wasm target:

cargo test -p worldgraph-wasm     # 14 native tests pin the Rust wire contract
cd supersplat-bridge && npm test  # 18 vitest tests; tsc --noEmit strict clean

The wasm32-gated bridge.rs cannot be compiled on the CI host here (no
wasm32-unknown-unknown target / wasm-pack), so it is verified by inspection;
all logic it calls is proven by the 14 native tests via the rlib path. A host
with the wasm toolchain runs worldgraph-wasm/build-wasm.sh to emit the module.

Notes

• No backend — everything runs in the tab.
• Privacy is structural: person nodes carry no identity; the audit card surfaces
  the privacy decision, not raw signals.
• The generated .wasm module and node_modules/lockfile-regenerated artifacts
  are git-ignored.

🤖 Generated with Claude Code

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Generated by Claude Code