Add MCP server for Claude Code memory integration

- Create stdio MCP server wrapping core memory functions (query, show, list, children, add, link)
- Add CLAUDE.md with memory-querying instructions for Claude
- Register MCP server in .mcp.json
- Document MCP setup and tools in USAGE.md

package.json

@@ -12,15 +12,18 @@
   "license": "ISC",
   "description": "AI project memory - knowledge graph backed by SQLite + Ollama embeddings",
   "bin": {
-    "memory": "./dist/cli/index.js"
+    "memory": "./dist/cli/index.js",
+    "memory-mcp": "./dist/mcp/index.js"
   },
   "dependencies": {
+    "@modelcontextprotocol/sdk": "^1.25.3",
     "better-sqlite3": "^12.6.2",
     "chalk": "^4.1.2",
     "commander": "^14.0.3",
     "cors": "^2.8.6",
     "express": "^5.2.1",
-    "uuid": "^13.0.0"
+    "uuid": "^13.0.0",
+    "zod": "^4.3.6"
   },
   "devDependencies": {
     "@types/better-sqlite3": "^7.6.13",