fix(node): retry rejected prev_chain_hash within a bounded submit budget; release 2.0.1

Claude-Session: https://claude.ai/code/session_01QoUjdc7HGKTsgj5GhG8HvF

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@elydora/sdk",
-  "version": "2.0.0",
+  "version": "2.0.1",
   "description": "Node.js/TypeScript SDK for the Elydora tamper-evident audit platform",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",