Introduce initial version of the Lonc app with core features, styling, and configurations.

- Add base app structure, including Bootstrap setup and Alpine.js integration.
- Implement authentication flow with session handling.
- Integrate stock management and label creation functionalities.
- Include responsive styling and theme using CSS variables and custom components.
- Add API clients for Tryton-based backend.
- Set up kitchen and dashboard navigation workflows.
- Configure service worker for PWA support.

src/components/app-shell.js

@@ -0,0 +1,28 @@
+import { navBar } from './nav-bar.js';
+
+export function appShell(appName) {
+  return `
+    <div class="app-shell d-flex flex-column min-vh-100">
+      ${navBar(appName)}
+      <main id="route-view" class="flex-grow-1"></main>
+      <div class="toast-stack" x-data="alertsData()">
+        <template x-for="alert in alerts" :key="alert.id">
+          <div class="toast show align-items-center border-0 mb-2 text-bg-dark" role="status">
+            <div class="d-flex">
+              <div class="toast-body">
+                <span class="badge me-2 text-uppercase" :class="badgeClass(alert.type)" x-text="alert.type"></span>
+                <span x-text="alert.message"></span>
+              </div>
+              <button
+                type="button"
+                class="btn-close btn-close-white me-2 m-auto"
+                @click="dismiss(alert.id)"
+                aria-label="Close"
+              ></button>
+            </div>
+          </div>
+        </template>
+      </div>
+    </div>
+  `;
+}