feat(ui): add GitHub source link button top-right

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gitverse",
-  "version": "0.7.0",
+  "version": "0.8.0-rc.0",
   "private": true,
   "type": "module",
   "scripts": {

src/ui/GithubLink.svelte

@@ -0,0 +1,29 @@
+<script lang="ts">
+  // Source repo — opens in a new tab. Icon-only button styled to match
+  // ResetButton; the inline octicon keeps it dependency- and network-free
+  // (matters for the offline PWA build).
+  const REPO_URL = 'https://github.com/opariffazman/gitverse';
+</script>
+
+<a
+  class="flex items-center justify-center rounded-lg border border-terminal-dim/40 bg-terminal-bg/80 p-1.5 text-terminal-dim hover:text-terminal-fg hover:border-terminal-dim/70 transition-colors backdrop-blur"
+  href={REPO_URL}
+  target="_blank"
+  rel="noopener noreferrer"
+  aria-label="View source on GitHub"
+  title="View source on GitHub"
+>
+  <svg
+    viewBox="0 0 16 16"
+    width="18"
+    height="18"
+    fill="currentColor"
+    aria-hidden="true"
+    focusable="false"
+  >
+    <path
+      fill-rule="evenodd"
+      d="M8 0C3.58 0 0 3.58 0 8c0 3.54 2.29 6.53 5.47 7.59.4.07.55-.17.55-.38 0-.19-.01-.82-.01-1.49-2.01.37-2.53-.49-2.69-.94-.09-.23-.48-.94-.82-1.13-.28-.15-.68-.52-.01-.53.63-.01 1.08.58 1.23.82.72 1.21 1.87.87 2.33.66.07-.52.28-.87.51-1.07-1.78-.2-3.64-.89-3.64-3.95 0-.87.31-1.59.82-2.15-.08-.2-.36-1.02.08-2.12 0 0 .67-.21 2.2.82.64-.18 1.32-.27 2-.27.68 0 1.36.09 2 .27 1.53-1.04 2.2-.82 2.2-.82.44 1.1.16 1.92.08 2.12.51.56.82 1.27.82 2.15 0 3.07-1.87 3.75-3.65 3.95.29.25.54.73.54 1.48 0 1.07-.01 1.93-.01 2.2 0 .21.15.46.55.38A8.013 8.013 0 0016 8c0-4.42-3.58-8-8-8z"
+    />
+  </svg>
+</a>

src/ui/Layout.svelte

@@ -2,17 +2,24 @@
   import Terminal from './Terminal.svelte';
   import Graph from './Graph.svelte';
   import ResetButton from './ResetButton.svelte';
+  import GithubLink from './GithubLink.svelte';
 </script>
 
 <div class="relative flex flex-col w-full h-full bg-terminal-bg">
-  <!-- Reset: top-left (logo sits top-right on desktop / top-center on mobile) -->
+  <!-- Reset: top-left. GitHub link: top-right corner. Logo sits between them
+       (just left of the link on desktop / top-center on mobile). -->
   <div class="absolute top-3 left-4 z-20">
     <ResetButton />
   </div>
 
-  <!-- Desktop: top-right -->
+  <!-- GitHub source link: top-right corner, above the decorative logo -->
+  <div class="absolute top-3 right-4 z-20">
+    <GithubLink />
+  </div>
+
+  <!-- Desktop: top-right, offset left so it clears the GitHub link button -->
   <pre
-    class="absolute top-3 right-4 z-10 font-mono text-terminal-dim/80 text-xs leading-tight select-none pointer-events-none max-sm:hidden">{` ██████╗ ██╗████████╗██╗   ██╗███████╗██████╗ ███████╗███████╗
+    class="absolute top-3 right-16 z-10 font-mono text-terminal-dim/80 text-xs leading-tight select-none pointer-events-none max-sm:hidden">{` ██████╗ ██╗████████╗██╗   ██╗███████╗██████╗ ███████╗███████╗
 ██╔════╝ ██║╚══██╔══╝██║   ██║██╔════╝██╔══██╗██╔════╝██╔════╝
 ██║  ███╗██║   ██║   ██║   ██║█████╗  ██████╔╝███████╗█████╗
 ██║   ██║██║   ██║   ╚██╗ ██╔╝██╔══╝  ██╔══██╗╚════██║██╔══╝

tests/e2e/a11y.spec.ts

@@ -170,3 +170,11 @@ test('unknown command shows a dim hint line', async ({ page }) => {
   await expect(page.getByText(/command not found/)).toBeVisible();
   await expect(page.getByText(/type 'help' to see available commands/)).toBeVisible();
 });
+
+test('GitHub source link points to the repo in a safe new tab', async ({ page }) => {
+  const link = page.getByRole('link', { name: 'View source on GitHub' });
+  await expect(link).toHaveAttribute('href', 'https://github.com/opariffazman/gitverse');
+  await expect(link).toHaveAttribute('target', '_blank');
+  // Opener isolation so the new tab can't navigate this one (tabnabbing).
+  await expect(link).toHaveAttribute('rel', /noopener/);
+});