fix: move fast-xml-parser to runtime dependencies

- Resolve import error when using JunitXmlFormatter
- Enable XML output functionality for published package

Author: steviec

package.json

@@ -41,6 +41,7 @@
     "ajv": "^8.12.0",
     "commander": "^12.0.0",
     "debug": "^4.3.0",
+    "fast-xml-parser": "^5.2.5",
     "yaml": "^2.0.0",
     "zod": "^3.25.76"
   },
@@ -53,7 +54,6 @@
     "@vitest/ui": "^3.2.4",
     "dotenv-cli": "^8.0.0",
     "eslint": "^9.30.1",
-    "fast-xml-parser": "^5.2.5",
     "globals": "^16.3.0",
     "lefthook": "^1.12.1",
     "prettier": "^3.6.2",