Preserve original transaction names when enriching (#1556)

* Preserve original transaction name

* Remove stale method

* Fix tests

db/migrate/20241218132503_add_enriched_name_field.rb

@@ -0,0 +1,37 @@
+class AddEnrichedNameField < ActiveRecord::Migration[7.2]
+  def change
+    add_column :account_entries, :enriched_name, :string
+
+    reversible do |dir|
+      dir.up do
+        execute <<-SQL
+          UPDATE account_entries ae
+          SET name = CASE ae.entryable_type
+            WHEN 'Account::Trade' THEN
+              CASE
+                WHEN EXISTS (
+                  SELECT 1 FROM account_trades t
+                  WHERE t.id = ae.entryable_id AND t.qty < 0
+                ) THEN 'Sell trade'
+                ELSE 'Buy trade'
+              END
+            WHEN 'Account::Transaction' THEN
+              CASE
+                WHEN ae.amount > 0 THEN 'Expense'
+                ELSE 'Income'
+              END
+            WHEN 'Account::Valuation' THEN 'Balance update'
+            ELSE 'Unknown entry'
+          END
+          WHERE name IS NULL
+        SQL
+
+        change_column_null :account_entries, :name, false
+      end
+
+      dir.down do
+        change_column_null :account_entries, :name, true
+      end
+    end
+  end
+end