[CL-637] icon api buttons links (#18388)

* update button api to accept icons

* use template outlet in button

* add link component

* create link component to handle anchors and buttons

* remove unnecessary let variables

* fix link focus state styling

* update link underline style

* fix broken skip link focus

* add focus method to link component

* fix typo

* fix off center loading state

* move flex styles to template to fix some minor style overrides

* remove unnecessary variables

* fix interaction states and add styles for test class to work properly

* refactor classes and make variable sreadonly

* fix classes not being applied correctly

* fix bad merge conflict resolution

* simplified button template

libs/components/src/button/button.component.html

@@ -1,6 +1,14 @@
-<span class="tw-relative">
-  <span [ngClass]="{ 'tw-invisible': showLoadingStyle() }">
-    <ng-content></ng-content>
+<span class="tw-relative tw-flex tw-items-center tw-justify-center">
+  <span [class.tw-invisible]="showLoadingStyle()" class="tw-flex tw-items-center tw-gap-2">
+    @if (startIcon()) {
+      <i class="{{ startIconClasses() }}"></i>
+    }
+    <div>
+      <ng-content></ng-content>
+    </div>
+    @if (endIcon()) {
+      <i class="{{ endIconClasses() }}"></i>
+    }
   </span>
   @if (showLoadingStyle()) {
     <span class="tw-absolute tw-inset-0 tw-flex tw-items-center tw-justify-center">