Implements issue #18 — unified persistent memory & spatial agentic
loop visualization:
- **Memory Graph** (`createMemoryGraph`): 9 typed nodes (user/feedback/
project/reference) as glowing pulsing spheres with labeled edges,
floating in the left wing of the Nexus at (-14, 2.5, -8). Nodes bob
and breathe independently; graph slowly sways on Y.
- **Sovereignty Loop** (`createSovereigntyLoop`): EXPORT → COMPRESS →
TRAIN → EVAL ring with stage nodes, halos, and a traveling pulse
sphere that changes color per stage. Central soul icosahedron pulses
at the core. Group slowly rotates.
- **HUD Legend**: top-right color key panel for memory node types and
sovereignty loop stages.
Fixes#18
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
