Enable noInvalidUseBeforeDeclaration lint rule

The var to let/const modernisation resolved all noInvalidUseBeforeDeclaration
violations by eliminating variable hoisting issues with proper block scoping.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: cressie176

biome.json

@@ -25,7 +25,7 @@
         "noInnerDeclarations": "error",
         "useParseIntRadix": "off",
         "noSwitchDeclarations": "off",
-        "noInvalidUseBeforeDeclaration": "off",
+        "noInvalidUseBeforeDeclaration": "error",
         "noPrecisionLoss": "off"
       },
       "style": {