Got the UI working

lib/redmine_qbo/hooks/issues_hook_listener.rb

@@ -64,7 +64,8 @@ module RedmineQbo
             locals: {
               search_customer: search_customer, 
               customer_id: customer_id, 
-              select_estimate: select_estimate
+              select_estimate: select_estimate,
+              f: context[:form]
             } 
           }
         )

lib/redmine_qbo/hooks/view_hook_listener.rb

@@ -16,11 +16,9 @@ module RedmineQbo
       # Load the javascript to support the autocomplete forms
       def view_layouts_base_html_head(context = {})
         safe_join([
-          '<script src="https://unpkg.com/@hotwired/stimulus/dist/stimulus.umd.js"></script>'.html_safe,  
           javascript_include_tag( 'application.js', plugin: :redmine_qbo),
           javascript_include_tag( 'autocomplete-rails.js', plugin: :redmine_qbo),
           javascript_include_tag( 'checkbox_controller.js', plugin: :redmine_qbo),
-          javascript_include_tag( 'index.js', plugin: :redmine_qbo),
           javascript_include_tag( 'nested_form_controller.js', plugin: :redmine_qbo)
         ])
       end

lib/redmine_qbo/patches/issue_patch.rb

@@ -23,6 +23,8 @@ module RedmineQbo
           belongs_to :customer_token, primary_key: :id
           belongs_to :estimate, primary_key: :id
           has_and_belongs_to_many :invoices
+          has_many :line_items, dependent: :destroy
+          accepts_nested_attributes_for :line_items, allow_destroy: true
 
           before_save :titlize_subject
           after_commit :enqueue_billing, on: :update