fix: add graceful error handling for get_budgets API errors

Returns informative error message when Monarch Money API fails,
which may occur if budgets are not configured in the account.

src/monarch_mcp_custom/server.py

@@ -110,7 +110,21 @@ async def get_transactions(
 async def get_budgets(reason: Optional[str] = None) -> str:
     """Get current budget information."""
     client = await get_authenticated_client()
-    budgets = await client.get_budgets()
+
+    try:
+        budgets = await client.get_budgets()
+    except Exception as e:
+        error_msg = str(e)
+        # Check if this is a Monarch API error about budgets not being set up
+        if "Something went wrong" in error_msg:
+            return serialize_json(
+                {
+                    "error": "Budget data unavailable",
+                    "detail": "The Monarch Money API returned an error. This may occur if budgets are not configured in your account.",
+                    "raw_error": error_msg,
+                }
+            )
+        raise
 
     # Build a category lookup from categoryGroups
     category_lookup = {}