feat: Vestige v2.0.0 "Cognitive Leap" — 3D dashboard, HyDE search, WebSocket events

The biggest release in Vestige history. Complete visual and cognitive overhaul.

Dashboard:
- SvelteKit 2 + Three.js 3D neural visualization at localhost:3927/dashboard
- 7 interactive pages: Graph, Memories, Timeline, Feed, Explore, Intentions, Stats
- WebSocket event bus with 16 event types, real-time 3D animations
- Bloom post-processing, GPU instanced rendering, force-directed layout
- Dream visualization mode, FSRS retention curves, command palette (Cmd+K)
- Keyboard shortcuts, responsive mobile layout, PWA installable
- Single binary deployment via include_dir! (22MB)

Engine:
- HyDE query expansion (intent classification + 3-5 semantic variants + centroid)
- fastembed 5.11 with optional Nomic v2 MoE + Qwen3 reranker + Metal GPU
- Emotional memory module (#29)
- Criterion benchmark suite

Backend:
- Axum WebSocket at /ws with heartbeat + event broadcast
- 7 new REST endpoints for cognitive operations
- Event emission from MCP tools via shared broadcast channel
- CORS for SvelteKit dev mode

Distribution:
- GitHub issue templates (bug report, feature request)
- CHANGELOG with comprehensive v2.0 release notes
- README updated with dashboard docs, architecture diagram, comparison table

734 tests passing, zero warnings, 22MB release binary.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/dashboard/static/manifest.json

@@ -0,0 +1,19 @@
+{
+	"name": "Vestige Memory Dashboard",
+	"short_name": "Vestige",
+	"description": "Cognitive memory visualization for AI agents",
+	"start_url": "/",
+	"display": "standalone",
+	"background_color": "#050510",
+	"theme_color": "#050510",
+	"icons": [
+		{
+			"src": "/favicon.svg",
+			"sizes": "any",
+			"type": "image/svg+xml",
+			"purpose": "any maskable"
+		}
+	],
+	"categories": ["developer", "utilities"],
+	"orientation": "any"
+}