Security fix: Remove hard-coded Moltbook API key (v1.0.5)

- Removed embedded API key from scripts/moltbook_post.py
- Script now requires explicit user configuration (env var or credentials file)
- Updated SKILL.md to clarify API key must be configured
- Core RAG functionality unaffected - fully local, no dependencies
- Addresses ClawHub security scan finding about embedded credentials

package.json

@@ -1,6 +1,6 @@
 {
   "name": "rag-openclaw",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "description": "RAG Knowledge System for OpenClaw - Semantic search across chat history, code, docs, and skills with automatic memory retrieval",
   "homepage": "http://git.theta42.com/nova/openclaw-rag-skill",
   "author": {