feat: sign in with passkeys, no password once an account has one; an account button and dialog in place of the sign-out button

internal/server/web/templates/dashboard.html

@@ -12,9 +12,7 @@
   <nav>
     <a href="/">Машины</a>
     <a href="/settings">Настройки</a>
-    <form method="post" action="/logout" style="display:inline; margin-left:22px">
-      <button class="btn ghost small" type="submit">Выйти</button>
-    </form>
+    <button type="button" class="btn ghost icon acct-btn" id="acct" title="Аккаунт" aria-label="Аккаунт"><svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="8" r="4"/><path d="M4 21a8 8 0 0 1 16 0"/></svg></button>
   </nav>
 </header>
 <div class="wrap">
@@ -100,5 +98,6 @@
   if (Object.keys(rows).length) schedule();
 })();
 </script>
+<script src="{{asset "account.js"}}"></script>
 </body>
 </html>