refactor: use bun for package management

+ add package.json to each packages
+ update import path

packages/game/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "@odyssey/game",
+  "version": "0.0.0",
+  "private": true,
+  "main": "index.ts",
+  "types": "index.ts",
+  "exports": {
+    ".": "./index.ts"
+  },
+  "dependencies": {
+    "@odyssey/file-graph": "workspace:*",
+    "zod": "^3.24.2",
+    "zod-to-json-schema": "^3.24.5"
+  }
+}