Allow user to add buy and sell trade transactions for investment accounts (#1066)

* Consolidate modal form structure into partial + helper

* Scaffold out trade transaction form

* Normalize translations

* Add buy and sell trade form with tests

* Move entryable lists to dedicated controllers

* Delegate entry group contents rendering

* More cleanup

* Extract transaction and valuation update logic from entries controller

* Delegate edit and show actions to entryables

* Trade builder

* Update paths for transaction updates

test/controllers/account/transactions_controller_test.rb

@@ -0,0 +1,40 @@
+require "test_helper"
+
+class Account::TransactionsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    sign_in @user = users(:family_admin)
+    @entry = account_entries :transaction
+  end
+
+  test "should get index" do
+    get account_transactions_url(@entry.account)
+    assert_response :success
+  end
+
+  test "update" do
+    assert_no_difference [ "Account::Entry.count", "Account::Transaction.count" ] do
+      patch account_transaction_url(@entry.account, @entry), params: {
+        account_entry: {
+          name: "Name",
+          date: Date.current,
+          currency: "USD",
+          amount: 100,
+          nature: "income",
+          entryable_type: @entry.entryable_type,
+          entryable_attributes: {
+            id: @entry.entryable_id,
+            tag_ids: [ Tag.first.id, Tag.second.id ],
+            category_id: Category.first.id,
+            merchant_id: Merchant.first.id,
+            notes: "test notes",
+            excluded: false
+          }
+        }
+      }
+    end
+
+    assert_equal "Transaction updated successfully.", flash[:notice]
+    assert_redirected_to account_entry_url(@entry.account, @entry)
+    assert_enqueued_with(job: AccountSyncJob)
+  end
+end