feat: move database migration link from account view to start view

- Remove database migration link from AccountViewView.vue
- Add new "Database Tools" section to StartView.vue
- Improve user flow by making database tools accessible from start page
- Maintain consistent styling and functionality
- Clean up account view to focus on account-specific settings

The database migration feature is now logically grouped with other
identity-related operations and more discoverable for users.

src/views/StartView.vue

@@ -82,6 +82,19 @@
             Derive new address from existing seed
           </a>
         </div>
+
+        <!-- Database Migration Section -->
+        <div class="mt-8 pt-6 border-t border-gray-200">
+          <p class="text-center text-lg font-light mb-4">Database Tools</p>
+          <div class="flex justify-center">
+            <router-link
+              :to="{ name: 'database-migration' }"
+              class="block w-fit text-center text-md bg-gradient-to-b from-slate-400 to-slate-700 shadow-[inset_0_-1px_0_0_rgba(0,0,0,0.5)] text-white px-4 py-2 rounded-md"
+            >
+              Database Migration
+            </router-link>
+          </div>
+        </div>
       </div>
     </div>
   </section>