feat(register): create @uncaged/workflow-register package

Merges bundle/ + registry/ + config/ modules. The config↔registry
circular dependency is resolved: ProviderConfig and WorkflowConfig
now come from @uncaged/workflow-protocol.

Ref: #143, closes #149

packages/workflow-register/package.json

@@ -0,0 +1,26 @@
+{
+  "name": "@uncaged/workflow-register",
+  "version": "0.1.0",
+  "type": "module",
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "import": "./src/index.ts"
+    }
+  },
+  "dependencies": {
+    "@uncaged/workflow-protocol": "workspace:*",
+    "@uncaged/workflow-util": "workspace:*"
+  },
+  "peerDependencies": {
+    "acorn": "^8.0.0",
+    "yaml": "^2.0.0",
+    "zod": "^4.0.0"
+  },
+  "devDependencies": {
+    "acorn": "^8.14.1",
+    "yaml": "^2.7.1",
+    "zod": "^4.0.0",
+    "typescript": "^5.8.3"
+  }
+}