Fail fast on missing terrain assets and recover empty renders

package.json

@@ -10,8 +10,10 @@
     "build": "next build",
     "start": "node scripts/supervise.mjs production",
     "setup": "node scripts/setup.mjs",
+    "reprocess": "node scripts/reprocess.mjs",
     "worker": "tsx worker/main.ts",
     "test": "tsx --test tests/*.test.ts",
+    "test:renderer": "node scripts/test-renderer.mjs",
     "test:e2e": "playwright test",
     "typecheck": "tsc --noEmit",
     "renderer:proof": "node scripts/proof.mjs",