fix: implement Blazor-native login form to properly update authentication state

Problem: JavaScript login form saved tokens to localStorage but didn't notify
CustomAuthenticationStateProvider, causing [Authorize] pages to remain in
'loading' state indefinitely. The provider only reads tokens when:
1. GetAuthenticationStateAsync() is called (page load)
2. NotifyAuthenticationStateChanged() is triggered (UI updates)

But JavaScript login didn't trigger either, leaving the authentication state
stale.

Solution: Convert AdminLoginForm from HTML+JavaScript to pure Blazor component.
Now the login flow is:
1. User enters credentials in Blazor form
2. HttpClient POST to /api/auth/login
3. Save tokens to localStorage
4. Call CustomAuthenticationStateProvider.LoginAsync() directly
5. Blazor detects auth state change and re-evaluates [Authorize] pages
6. Dashboard [Authorize] page renders successfully

Result: Immediate authentication state update, no loading timeout on protected pages.

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

legacy/smartadmin/scripts/pages/smarttablesimportexportdata.js

@@ -0,0 +1,53 @@
+import { SmartTables } from '../optional/smartTables/smartTables.bundle.js';
+
+// Wait for the DOM to load before initializing
+document.addEventListener('DOMContentLoaded', () => {
+    const importBtn = document.getElementById('importBtn');
+    const tableContainer = document.getElementById('tableContainer');
+    let table = null;
+    let errorContainer = document.getElementById('errorContainer');
+
+    // Initialize the table immediately but keep the container hidden
+    table = new SmartTables('myTable', {
+        import: true,
+        export: true,
+        responsive: {
+            enabled: true,
+            breakpoint: 768
+        }
+    });
+
+    // Handle import button click
+    importBtn.addEventListener('click', () => {
+
+        // Hide the import data container
+        const hideImportData = document.getElementById('hide-import-data');
+        hideImportData.classList.add('d-none');
+
+        // Show the table container
+        tableContainer.classList.remove('d-none');
+        
+        try {
+            // First, create the import modal if it doesn't exist
+            if (typeof table.createImportModal === 'function') {
+                table.createImportModal();
+                
+                // Now find the modal and show it using Bootstrap's Modal API
+                const importModal = document.getElementById('importModal');
+                if (importModal) {
+                    // Create a new Bootstrap modal instance and show it
+                    const bsModal = new bootstrap.Modal(importModal);
+                    bsModal.show();
+                    console.log('Import modal opened successfully');
+                } else {
+                    throw new Error('Import modal element not found after creation');
+                }
+            } else {
+                throw new Error('createImportModal method not found on table instance');
+            }
+        } catch (error) {
+            console.error('Failed to open import modal:', error);
+            errorContainer.classList.remove('d-none');
+        }
+    });
+});