feat: add QR scanner, improve UX, and simplify navigation

- Add live camera QR scanner for nsec/ncryptsec login
- Replace browser prompt() with proper password dialog for ncryptsec
- Add missing /notes/:id route for thread view navigation
- Remove explore section entirely (button, page, routes)
- Remove profile button from bottom nav, avatar now opens profile
- Remove "Notes" tab from feed, default to showing all posts/replies
- Add PasswordPromptProvider for secure password input
- Add SidebarDrawer for mobile navigation
- Add domain layer with value objects and adapters
- Various UI and navigation improvements

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

index.html

@@ -12,6 +12,9 @@
     />
 
     <meta name="apple-mobile-web-app-title" content="Smesh" />
+    <link rel="preconnect" href="https://fonts.googleapis.com" />
+    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
+    <link href="https://fonts.googleapis.com/css2?family=Noto+Sans:ital,wght@0,100..900;1,100..900&display=swap" rel="stylesheet" />
     <link rel="icon" href="/favicon.ico" sizes="48x48" />
     <link rel="icon" href="/favicon.png" sizes="256x256" type="image/png" />
     <meta name="theme-color" content="#171717" media="(prefers-color-scheme: dark)" />