chore(styles): Added missing stencil components to the list of initia…

…lly hidden ones (#4544)

Co-authored-by: Alizé Debray <[email protected]>

.changeset/eighty-bees-invent.md

@@ -0,0 +1,5 @@
+---
+'@swisspost/design-system-styles': patch
+---
+
+Made the following components hidden until fully loaded to prevent flickering: `post-avatar`, `post-banner`, `post-breadcrumb`, `post-breadcrumb-item`, `post-closebutton`, `post-collapsible-trigger`, `post-footer`, `post-header`, `post-language-option`, `post-language-switch`, `post-mainnavigation`, `post-megadropdown`, `post-megadropdown-trigger`, `post-menu`, `post-menu-item`, and `post-menu-trigger`.

packages/styles/src/utilities/_not-defined.scss

@@ -3,23 +3,40 @@
 */
 
 :where(
-    post-list,
-    post-list-item,
     post-accordion,
     post-accordion-item,
     post-alert,
+    post-avatar,
     post-back-to-top,
+    post-banner,
+    post-breadcrumb,
+    post-breadcrumb-item,
     post-card-control,
+    post-closebutton,
     post-collapsible,
+    post-collapsible-trigger,
+    post-footer,
+    post-header,
     post-icon,
+    post-language-option,
+    post-language-switch,
+    post-list,
+    post-list-item,
     post-logo,
+    post-mainnavigation,
+    post-megadropdown,
+    post-megadropdown-trigger,
+    post-menu,
+    post-menu-item,
+    post-menu-trigger,
     post-popover,
     post-popovercontainer,
     post-rating,
     post-tab-header,
     post-tab-panel,
     post-tabs,
     post-tag,
+    post-togglebutton,
     post-tooltip
   ):not(:defined) {
   visibility: hidden;