docs(spikes): Deno 2.9.7 + TS 7 compatibility spike and ADR-004

Co-Authored-By: Claude Fable 5.1 <[email protected]>

spikes/deno/packages/contracts/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "@umt/contracts",
+  "version": "0.0.0",
+  "private": true,
+  "type": "module",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "scripts": {
+    "typecheck": "tsc -p tsconfig.json",
+    "test": "vitest run"
+  },
+  "dependencies": {
+    "zod": "^4.3.6"
+  }
+}