Account namespace updates: part 4 (transfers, singular namespacing) (#896)

* Move Transfer to Account namespace

* Fix partial resolution due to namespacing plurality

* Make category and tag controllers consistent with namespacing convention

* Update stale partial reference

app/controllers/transaction/rows_controller.rb

@@ -0,0 +1,22 @@
+class Transaction::RowsController < ApplicationController
+  before_action :set_transaction, only: %i[ show update ]
+
+  def show
+  end
+
+  def update
+    @transaction.update! transaction_params
+
+    redirect_to transaction_row_path(@transaction)
+  end
+
+  private
+
+    def transaction_params
+      params.require(:transaction).permit(:category_id)
+    end
+
+    def set_transaction
+      @transaction = Current.family.transactions.find(params[:id])
+    end
+end