Update branding with DockMV logo and assets

- Replace text-based branding with logo icon in header
- Update README.md with full DockMV logo image
- Add favicon and logo-icon assets
- Add dockmv-icon to assets directory
- Update styles for logo display
- Rebuild web UI distribution

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

web/src/App.tsx

@@ -120,7 +120,7 @@ export default function App() {
   return (
     <div className="app">
       <header className="topbar">
-        <div className="brand"><span className="dot" />docker-migrate</div>
+        <div className="brand"><img src="/logo-icon.png" alt="" className="brand-logo" />DockMV</div>
         <nav className="tabs">
           <button className={`tab${view === 'containers' ? ' active' : ''}`} onClick={() => setView('containers')}>
             Containers

web/src/styles.css

@@ -58,7 +58,7 @@ button, input, select, textarea { font: inherit; color: inherit; }
   font-family: var(--mono); font-weight: 600; letter-spacing: -0.3px;
   display: flex; align-items: center; gap: 8px;
 }
-.brand .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); }
+.brand-logo { height: 22px; width: auto; display: block; }
 
 .tabs { display: flex; gap: 2px; margin-left: 8px; }
 .tab {