docs(project): add reference Python/Flask implementation

Previous version of Tanabata used as visual and functional reference
for the new Go + SvelteKit rewrite.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/reference/web/static/service/browserconfig.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<browserconfig>
+    <msapplication>
+        <tile>
+            <square70x70logo src="/images/ms-icon-70x70.png" />
+            <square150x150logo src="/images/ms-icon-150x150.png" />
+            <square310x310logo src="/images/ms-icon-310x310.png" />
+            <TileColor>#615880</TileColor>
+        </tile>
+    </msapplication>
+</browserconfig>