fix(types): dispatched events without a detail value should be null (#1124)

Currently, dispatched events without `e.detail` have a type of `any`.

We can be more specific as a `CustomEvent` detail value is `null`.

src/ImageLoader/ImageLoader.svelte

@@ -1,7 +1,7 @@
 <script>
   /**
-   * @event {any} load
-   * @event {any} error
+   * @event {null} load
+   * @event {null} error
    */
 
   /**

src/LocalStorage/LocalStorage.svelte

@@ -1,6 +1,6 @@
 <script>
   /**
-   * @event {any} save
+   * @event {null} save
    * @event {{ prevValue: any; value: any; }} update
    */
 

src/MultiSelect/MultiSelect.svelte

@@ -8,7 +8,7 @@
    * @typedef {string} MultiSelectItemText
    * @typedef {{ id: MultiSelectItemId; text: MultiSelectItemText; }} MultiSelectItem
    * @event {{ selectedIds: MultiSelectItemId[]; selected: MultiSelectItem[]; unselected: MultiSelectItem[]; }} select
-   * @event {any} clear
+   * @event {null} clear
    */
 
   /**

src/Search/Search.svelte

@@ -1,7 +1,7 @@
 <script>
   /**
-   * @event {any} expand
-   * @event {any} collapse
+   * @event {null} expand
+   * @event {null} collapse
    */
 
   /**

src/Tooltip/Tooltip.svelte

@@ -1,7 +1,7 @@
 <script>
   /**
-   * @event {any} open
-   * @event {any} close
+   * @event {null} open
+   * @event {null} close
    */
 
   /**

src/TooltipDefinition/TooltipDefinition.svelte

@@ -1,7 +1,7 @@
 <script>
   /**
-   * @event {any} open
-   * @event {any} close
+   * @event {null} open
+   * @event {null} close
    */
 
   /** Specify the tooltip text */

src/UIShell/HeaderSearch.svelte

@@ -1,9 +1,9 @@
 <script>
   /**
    * @typedef {{ href: string; text: string; description?: string; }} HeaderSearchResult
-   * @event {any} active
-   * @event {any} inactive
-   * @event {any} clear
+   * @event {null} active
+   * @event {null} inactive
+   * @event {null} clear
    * @event {{ value: string; selectedResultIndex: number; selectedResult: HeaderSearchResult }} select
    * @slot {{ result: HeaderSearchResult; index: number }}
    */

src/UIShell/SideNav/SideNav.svelte

@@ -1,8 +1,8 @@
 <script>
   /**
-   * @event {any} open
-   * @event {any} close
-   * @event {any} click:overlay
+   * @event {null} open
+   * @event {null} close
+   * @event {null} click:overlay
    */
 
   /** Set to `true` to use the fixed variant */