Phase 2: 3D live map driven by API WebSocket

- apps/live-map/src/hooks/useLiveState.ts: WebSocket subscription
  with exponential-backoff reconnect, polling fallback, status tracking
- apps/live-map/src/scene/Scene.tsx: refactored Three.js scene with
  per-frame orbit propagation, vessel marker color-coding by owner,
  orbit-line visibility tied to focus filters, smooth camera follow
  on selected vessel/body
- apps/live-map/src/scene/layout.ts: bodyPositionAt / vesselPositionAt
  helpers (heliocentric frame, walk up the parent chain), logScale
  helpers for the system view
- apps/live-map/src/scene/color.ts: per-body and per-owner color maps
- apps/live-map/src/panels/TimeControls.tsx: play/pause/reverse/reset
  buttons, ×1/×10/×100/×1k/×10k/×100k speeds, UT scrub slider,
  live-edge indicator (LIVE / Nh behind / Nh ahead)
- apps/live-map/src/panels/VesselList.tsx: vessel sidebar with click-
  to-track; color-coded by owner (KASA=blue, SPES=orange)
- apps/live-map/src/panels/FocusPanel.tsx: planet/moon/vessel orbit
  visibility toggles
- apps/live-map/src/panels/StatusPill.tsx: WS status (LIVE/POLLING/
  OFFLINE/STALE), body + vessel + message counts
- tests/scene.test.ts: 10 tests for layout helpers (periodicity,
  vessel-centered positioning, logScale round-trips)

End-to-end verified: mock publisher → API → live-map WebSocket →
scene re-renders with the new vessel positions and orbits.

apps/live-map/package.json

@@ -10,7 +10,7 @@
     "preview": "vite preview --port 3001",
     "typecheck": "tsc --noEmit",
     "lint": "echo 'no linter yet'",
-    "test": "echo 'no tests yet'"
+    "test": "vitest run"
   },
   "dependencies": {
     "@kerbal-rt/shared-types": "workspace:*",
@@ -26,6 +26,7 @@
     "@types/three": "^0.169.0",
     "@vitejs/plugin-react": "^4.3.1",
     "typescript": "^5.6.2",
-    "vite": "^5.4.6"
+    "vite": "^5.4.6",
+    "vitest": "^2.1.1"
   }
 }