feat(auth): add session-based login/logout with bcrypt hashing, seed default admin, templates and navbar updates; add auth middleware; pin SQLAlchemy 1.4.x for Py3.13; update TODOs

app/templates/base.html

@@ -43,10 +43,10 @@
                 </ul>
 
                 <ul class="navbar-nav">
-                    {% if 'user' in session %}
+                    {% if request.session.get('user') %}
                     <li class="nav-item dropdown">
                         <a class="nav-link dropdown-toggle" href="#" id="userDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false">
-                            <i class="bi bi-person-circle me-1"></i>{{ session.user.username }}
+                            <i class="bi bi-person-circle me-1"></i>{{ request.session.get('user').username if request.session.get('user') else '' }}
                         </a>
                         <ul class="dropdown-menu" aria-labelledby="userDropdown">
                             <li><a class="dropdown-item" href="/profile">Profile</a></li>

app/templates/login.html

@@ -1 +1,111 @@
-<!-- Login form template -->
+{% extends "base.html" %}
+
+{% block title %}Login - Delphi Database{% endblock %}
+
+{% block content %}
+<div class="container">
+    <div class="row justify-content-center">
+        <div class="col-md-6 col-lg-4">
+            <div class="card shadow-sm">
+                <div class="card-body">
+                    <div class="text-center mb-4">
+                        <img src="{{ url_for('static', path='/logo/delphi-logo.webp') }}" alt="Delphi Logo" class="mb-3" style="width: 60px; height: 60px;">
+                        <h2 class="card-title">Welcome Back</h2>
+                        <p class="text-muted">Sign in to access Delphi Database</p>
+                    </div>
+
+                    {% if error %}
+                    <div class="alert alert-danger" role="alert">
+                        <i class="bi bi-exclamation-triangle-fill me-2"></i>{{ error }}
+                    </div>
+                    {% endif %}
+
+                    <form method="post" action="/login">
+                        <div class="mb-3">
+                            <label for="username" class="form-label">Username</label>
+                            <div class="input-group">
+                                <span class="input-group-text"><i class="bi bi-person"></i></span>
+                                <input type="text" class="form-control" id="username" name="username" required
+                                       placeholder="Enter your username" autocomplete="username">
+                            </div>
+                        </div>
+
+                        <div class="mb-3">
+                            <label for="password" class="form-label">Password</label>
+                            <div class="input-group">
+                                <span class="input-group-text"><i class="bi bi-key"></i></span>
+                                <input type="password" class="form-control" id="password" name="password" required
+                                       placeholder="Enter your password" autocomplete="current-password">
+                            </div>
+                        </div>
+
+                        <div class="mb-3 form-check">
+                            <input type="checkbox" class="form-check-input" id="rememberMe">
+                            <label class="form-check-label" for="rememberMe">
+                                Remember me
+                            </label>
+                        </div>
+
+                        <div class="d-grid">
+                            <button type="submit" class="btn btn-primary">
+                                <i class="bi bi-box-arrow-in-right me-2"></i>Sign In
+                            </button>
+                        </div>
+                    </form>
+
+                    <div class="text-center mt-4">
+                        <small class="text-muted">
+                            <i class="bi bi-info-circle me-1"></i>
+                            Default credentials: admin / admin123
+                        </small>
+                    </div>
+                </div>
+            </div>
+
+            <div class="text-center mt-3">
+                <small class="text-muted">
+                    Don't have an account? Contact your administrator.
+                </small>
+            </div>
+        </div>
+    </div>
+</div>
+{% endblock %}
+
+{% block extra_scripts %}
+<script>
+// Auto-focus on username field
+document.addEventListener('DOMContentLoaded', function() {
+    document.getElementById('username').focus();
+});
+
+// Show/hide password toggle (optional enhancement)
+document.addEventListener('DOMContentLoaded', function() {
+    const passwordField = document.getElementById('password');
+    const toggleBtn = document.createElement('button');
+    toggleBtn.type = 'button';
+    toggleBtn.className = 'btn btn-outline-secondary';
+    toggleBtn.innerHTML = '<i class="bi bi-eye"></i>';
+    toggleBtn.style.border = 'none';
+    toggleBtn.style.background = 'transparent';
+
+    // Add toggle functionality
+    toggleBtn.addEventListener('click', function() {
+        if (passwordField.type === 'password') {
+            passwordField.type = 'text';
+            this.innerHTML = '<i class="bi bi-eye-slash"></i>';
+        } else {
+            passwordField.type = 'password';
+            this.innerHTML = '<i class="bi bi-eye"></i>';
+        }
+    });
+
+    // Insert toggle button into password input group
+    const passwordInputGroup = passwordField.closest('.input-group');
+    if (passwordInputGroup) {
+        const span = passwordInputGroup.querySelector('.input-group-text');
+        passwordInputGroup.insertBefore(toggleBtn, span.nextSibling);
+    }
+});
+</script>
+{% endblock %}