Phone App: rename Dart package to drivervault_phone

Follows the Android package rename: updates the pubspec name, the
package: imports in the tests, the web title/manifest strings, and the
project name in the README.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Phone App/web/index.html

@@ -23,13 +23,13 @@
   <!-- iOS meta tags & icons -->
   <meta name="mobile-web-app-capable" content="yes">
   <meta name="apple-mobile-web-app-status-bar-style" content="black">
-  <meta name="apple-mobile-web-app-title" content="carcontrol_phone">
+  <meta name="apple-mobile-web-app-title" content="drivervault_phone">
   <link rel="apple-touch-icon" href="icons/Icon-192.png">
 
   <!-- Favicon -->
   <link rel="icon" type="image/png" href="favicon.png"/>
 
-  <title>carcontrol_phone</title>
+  <title>drivervault_phone</title>
   <link rel="manifest" href="manifest.json">
 </head>
 <body>