fix: Rename "Other" group to "Uncategorized" and fix Cash & ATM placement

Changed the default group name from "Other" to "Uncategorized" to better
reflect its purpose, and moved "Cash & ATM" from being its own group to
being a category under the Financial group, matching Monarch defaults.

Changes:
- Renamed "Other" group → "Uncategorized"
- Removed "Cash & ATM" as a separate group
- Moved "Cash & ATM" category to Financial group (per Monarch defaults)
- "Check" now only in Uncategorized group (removed from Cash & ATM)
- Updated tests to expect "Uncategorized" group name

This makes the group hierarchy clearer and matches Monarch's structure.

All tests pass.

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

Co-Authored-By: Claude <noreply@anthropic.com>

Author: wesm

moneyflow/categories.py

@@ -106,8 +106,7 @@
         "Insurance",
         "Taxes",
     ],
-    "Other": [
-        "Other",
+    "Uncategorized": [
         "Uncategorized",
         "Check",
         "Miscellaneous",

tests/test_amazon_orders_importer.py

@@ -510,8 +510,8 @@ async def test_fetch_all_data_workflow(self, sample_orders_csv, temp_db):
         assert "cat_uncategorized" in categories
 
         # Verify group was derived from category
-        # Monarch defaults have "Other" group containing "Uncategorized" category
-        assert all(df["group"] == "Other")  # All initially in Other group
+        # "Uncategorized" category is in "Uncategorized" group
+        assert all(df["group"] == "Uncategorized")  # All initially in Uncategorized group
 
     @pytest.mark.asyncio
     async def test_fetch_respects_date_filters(self, sample_orders_csv, temp_db):