Add Streamable HTTP transport for remote MCP access

- Convert from stdio-only to dual-mode (stdio + HTTP)
- Add Express server with /mcp endpoint for Streamable HTTP
- Add /health endpoint for Railway health checks
- Update MCP SDK to v1.12.0 for Streamable HTTP support
- Add railway.toml for Railway deployment
- Default to HTTP mode, use --stdio flag for local mode

package.json

@@ -43,14 +43,16 @@
     "node": ">=18.0.0"
   },
   "dependencies": {
-    "@modelcontextprotocol/sdk": "^1.8.0",
+    "@modelcontextprotocol/sdk": "^1.12.0",
     "axios": "^1.8.4",
     "dotenv": "^16.4.7",
+    "express": "^4.21.2",
     "node-fetch": "^3.3.2",
     "openai": "^4.89.1",
     "sharp": "^0.33.5"
   },
   "devDependencies": {
+    "@types/express": "^5.0.0",
     "@types/node": "^22.13.14",
     "@types/sharp": "^0.32.0",
     "shx": "^0.3.4",