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/dees-modal/dees-modal.ts

@@ -21,6 +21,7 @@ import {
 import * as domtools from '@design.estate/dees-domtools';
 import { DeesWindowLayer } from '../dees-windowlayer/dees-windowlayer.js';
 import '../dees-icon/dees-icon.js';
+import { themeDefaultStyles } from '../00theme.js';
 
 declare global {
   interface HTMLElementTagNameMap {
@@ -115,8 +116,10 @@ export class DeesModal extends DeesElement {
   }
 
   public static styles = [
+    themeDefaultStyles,
     cssManager.defaultStyles,
     css`
+      /* TODO: Migrate hardcoded values to --dees-* CSS variables */
       :host {
         font-family: ${cssGeistFontFamily};
         color: ${cssManager.bdTheme('#333', '#fff')};