add entry requests, invite new users

db/migrate/20260129204706_add_requested_by_to_entries.rb

@@ -0,0 +1,7 @@
+class AddRequestedByToEntries < ActiveRecord::Migration[8.1]
+  def change
+    add_column :entries, :requested_by_id, :integer
+    add_foreign_key :entries, :users, column: :requested_by_id
+    add_index :entries, :requested_by_id
+  end
+end