Implement comprehensive project time logging feature

Add complete project management system with role-based access control:

**Core Features:**
- Project creation and management for Admins/Supervisors
- Time tracking with optional project selection and notes
- Project-based filtering and reporting in history
- Enhanced export functionality with project data
- Team-specific project assignments

**Database Changes:**
- New Project model with full relationships
- Enhanced TimeEntry model with project_id and notes
- Updated migration scripts with rollback support
- Sample project creation for testing

**User Interface:**
- Project management templates (create, edit, list)
- Enhanced time tracking with project dropdown
- Project filtering in history page
- Updated navigation for role-based access
- Modern styling with hover effects and responsive design

**API Enhancements:**
- Project validation and access control
- Updated arrive endpoint with project support
- Enhanced export functions with project data
- Role-based route protection

**Migration Support:**
- Comprehensive migration scripts (migrate_projects.py)
- Updated main migration script (migrate_db.py)
- Detailed migration documentation
- Rollback functionality for safe deployment

**Role-Based Access:**
- Admins: Full project CRUD operations
- Supervisors: Project creation and management
- Team Leaders: View team hours with projects
- Team Members: Select projects when tracking time

🤖 Generated with [Claude Code](https://claude.ai/code)

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

templates/layout.html

@@ -23,6 +23,14 @@
                             <li><a href="{{ url_for('profile') }}">Profile</a></li>
                             <li><a href="{{ url_for('config') }}">Config</a></li>
                             <li><a href="{{ url_for('dashboard') }}">Dashboard</a></li>
+                            <li><a href="{{ url_for('admin_dashboard') }}">Admin Dashboard</a></li>
+                            <li><a href="{{ url_for('admin_users') }}">Manage Users</a></li>
+                            <li><a href="{{ url_for('admin_teams') }}">Manage Teams</a></li>
+                            <li><a href="{{ url_for('admin_projects') }}">Manage Projects</a></li>
+                            <li><a href="{{ url_for('admin_settings') }}">System Settings</a></li>
+                            {% if g.user.team_id %}
+                            <li><a href="{{ url_for('team_hours') }}">Team Hours</a></li>
+                            {% endif %}
                             <li><a href="{{ url_for('logout') }}">Logout</a></li>
                         </ul>
                     </li>
@@ -34,6 +42,9 @@
                             <li><a href="{{ url_for('profile') }}">Profile</a></li>
                             <li><a href="{{ url_for('config') }}">Config</a></li>
                             <li><a href="{{ url_for('dashboard') }}">Dashboard</a></li>
+                            {% if g.user.role == Role.SUPERVISOR %}
+                            <li><a href="{{ url_for('admin_projects') }}">Manage Projects</a></li>
+                            {% endif %}
                             {% if g.user.team_id %}
                             <li><a href="{{ url_for('team_hours') }}">Team Hours</a></li>
                             {% endif %}