Update extension "engines.vscode" to "^1.115.0"

Updates the minimum required "engines.vscode" version from
"^1.110.0" to "^1.115.0" in order to align with newer @types/vscode.

Author: data-douser

extensions/vscode/package.json

@@ -16,7 +16,7 @@
     "url": "https://github.com/advanced-security/codeql-development-mcp-server/issues"
   },
   "engines": {
-    "vscode": "^1.110.0",
+    "vscode": "^1.115.0",
     "node": ">=24.13.0"
   },
   "categories": [