release: rename package @a2a/mcp → @a2amcp/mcp, bump to 0.1.1

The @a2a scope on npm is owned by a different account, so PUT against
the registry 404'd. Move to @a2amcp/mcp (scope we control) and bump the
version so the publish workflow has a fresh tag to push.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

package-lock.json

@@ -1,12 +1,12 @@
 {
-  "name": "@a2a/mcp",
-  "version": "0.1.0",
+  "name": "@a2amcp/mcp",
+  "version": "0.1.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
-      "name": "@a2a/mcp",
-      "version": "0.1.0",
+      "name": "@a2amcp/mcp",
+      "version": "0.1.1",
       "license": "Apache-2.0",
       "dependencies": {
         "@modelcontextprotocol/sdk": "^1.0.4",