feat(standard-styling) Enhance search and styling

Improves search bar with SVG icon support for better visual consistency.

Adds utility SCSS file for managing global styles like heading selectors.

Introduces a checkmark SVG asset and reorganizes custom SCSS files following the 7-in-1 structure for better maintainability.

Comments out optional USP bar code in header.tpl to allow easy activation.

falcon/modules/is_searchbar/views/templates/hook/is_searchbar.tpl

@@ -9,7 +9,12 @@
 					   name="s"
 					   value="{$search_string}">
 				<button type="submit" class="search-form__btn btn">
-					<span class="material-icons">search</span>
+                    {capture name="svg_output"}{svg_icon file='search.svg'}{/capture}
+                    {if $smarty.capture.svg_output}
+                        {$smarty.capture.svg_output nofilter}
+                    {else}
+                        <span class="header-top__icon material-icons">search</span>
+                    {/if}
 				</button>
 			</div>
 		</form>