feat: gallery + generic blueprint viewer, add Grid blueprint

Refactor the List-specific screen into a data-driven, reusable viewer:
- generic Blueprint type + shared LoadState machine + registry
- vue-router: / (gallery) and /b/:slug (illustration)
- BlueprintViewer renders any blueprint; specimens stay bespoke
- add Grid blueprint (6 functions incl. Position) + GridSpecimen

package.json

@@ -14,7 +14,8 @@
   },
   "dependencies": {
     "daisyui": "^5.6.6",
-    "vue": "^3.5.39"
+    "vue": "^3.5.39",
+    "vue-router": "^5.1.0"
   },
   "devDependencies": {
     "@tailwindcss/vite": "^4.3.2",