feat(theme,interfaces): Introduce a global theming system and unify menu/tab interfaces; migrate components to use themeDefaultStyles and update APIs accordingly

ts_web/elements/00group-form/dees-form-submit/dees-form-submit.ts

@@ -8,6 +8,7 @@ import {
   property,
 } from '@design.estate/dees-element';
 import type { DeesForm } from '../dees-form/dees-form.js';
+import { themeDefaultStyles } from '../../00theme.js';
 
 declare global {
   interface HTMLElementTagNameMap {
@@ -39,7 +40,9 @@ export class DeesFormSubmit extends DeesElement {
     super();
   }
   
-  public static styles = [cssManager.defaultStyles, css``];
+  public static styles = [themeDefaultStyles, cssManager.defaultStyles, css`
+      /* TODO: Migrate hardcoded values to --dees-* CSS variables */
+    `];
 
   public render() {
     return html`