add tags stories

stories/tags.stories.svelte

@@ -0,0 +1,31 @@
+<script context="module">
+
+    import { Story, Template } from '../src/index';
+
+    /**
+     * Testing tags parsing in the addon's indexer.
+     * - In the sidebar, only the _"With Dev"_ story should be visible.
+     * - In docs, only the _"With Autodocs"_ story should be visible.
+     */
+    export const meta ={
+      title: 'Tags',
+      parameters: {
+        controls: { disable: true },
+      },
+      tags: ['meta-first', '!meta-second', '!meta-third'],
+    };
+  </script>
+
+  <Template let:context>
+    <h1>Tags:</h1>
+    <pre><code>{JSON.stringify(context.tags, null, 2)}</code></pre>
+  </Template>
+
+  <Story name="No Story Tags" />
+
+  <Story name="With story tag" tags={['story-first']} />
+
+  <Story name="With story tag, meta disabled" tags={['story-first', '!meta-first']} />
+
+  <Story name="With story tag, meta enabled" tags={['story-first', 'meta-second']} />
+