feat: remove the retired Mermaid Chart Playground from the Share dialog

The playground has been retired, so the Share dialog no longer offers a
link to it and only lists the Live Editor link and the embed section.
The now-unused "share" analytics medium goes with it; the playground URL
itself stays until the main menu entry is removed separately.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/lib/components/Share.svelte

@@ -8,16 +8,14 @@
   import { MERMAID_LOOKS, MERMAID_THEMES, TID } from '$/constants';
   import { isDarkTheme, type EmbedMode } from '$/util/embed';
   import { EMBED_IFRAME_SANDBOX, buildEmbedSnippets, buildEmbedUrls } from '$/util/embedCode';
-  import { env } from '$/util/env';
   import { silentlySanitizeConfig } from '$/util/sanitize';
-  import { urls, validatedState } from '$/util/state.svelte';
+  import { validatedState } from '$/util/state.svelte';
   import { copyToClipboard } from '$/util/util';
   import { asset, base } from '$app/paths';
   import CodeIcon from '~icons/material-symbols/code';
   import ShareIcon from '~icons/material-symbols/share';
   import CopyButton from './CopyButton.svelte';
   import CopyInput from './CopyInput.svelte';
-  import MermaidChartIcon from './MermaidChartIcon.svelte';
 
   const sanitizedConfig = $derived(silentlySanitizeConfig(validatedState.current.mermaid));
   // Deliberate initial-value capture: the embed form seeds from the config at
@@ -74,19 +72,6 @@
           The content of the diagrams you create never leaves your browser.
         </Dialog.Description>
       </div>
-      {#if env.isEnabledMermaidChartLinks}
-        <Separator />
-        <div class="flex flex-col gap-2">
-          <h2 class="flex items-center gap-2">
-            <MermaidChartIcon class="size-5" />
-            Mermaid Chart Playground
-          </h2>
-          <CopyInput value={urls.current.mermaidChart({ medium: 'share' }).playground} />
-          <Dialog.Description>
-            Opens the Mermaid Chart Playground with Mermaid AI, Visual Editor, and more.
-          </Dialog.Description>
-        </div>
-      {/if}
       <Separator />
       <div class="flex flex-col gap-3">
         <h2 class="flex items-center gap-2">

src/lib/util/state.svelte.ts

@@ -164,7 +164,6 @@ const urlsCurrent = $derived.by(() => {
         | 'ai_repair'
         | 'main_menu'
         | 'save_diagram'
-        | 'share'
         | 'vibe_diagramming'
         | 'visual_edit'
         | 'voice_edit';

tests/embed.spec.ts

@@ -98,6 +98,16 @@ base.describe('Embed page', () => {
 });
 
 editorTest.describe('Share dialog embed section', () => {
+  editorTest('should only offer the live editor link and the embed', async ({ editPage, page }) => {
+    void editPage;
+    await page.getByRole('button', { name: 'Share' }).click();
+    const dialog = page.getByRole('dialog');
+    await expect(dialog.getByRole('heading', { name: 'Mermaid Live Editor' })).toBeVisible();
+    await expect(dialog.getByRole('heading', { name: 'Embed' })).toBeVisible();
+    // The Mermaid Chart Playground is retired and must not be offered any more.
+    await expect(dialog).not.toContainText('Playground');
+  });
+
   editorTest('should offer iframe and web component snippets', async ({ editPage, page }) => {
     void editPage;
     await page.getByRole('button', { name: 'Share' }).click();