feat(ui): graph on d3-force with steady labels, quieter quota text, flat rail

ui/package.json

@@ -14,6 +14,7 @@
     "preview": "vite preview"
   },
   "dependencies": {
+    "d3-force": "^3.0.0",
     "dompurify": "^3.4.14",
     "marked": "^18.0.11"
   },
@@ -28,6 +29,7 @@
     "@tailwindcss/forms": "^0.5.11",
     "@tailwindcss/typography": "^0.5.19",
     "@tailwindcss/vite": "^4.3.0",
+    "@types/d3-force": "^3.0.10",
     "@types/node": "^26.4.0",
     "bits-ui": "^2.19.0",
     "clsx": "^2.1.1",