feat: add 'Manager' link to Header component

- Introduced a new navigation link for the 'Manager' page in the Header component, improving user access to management features.

components/ui/Header.tsx

@@ -54,6 +54,7 @@ export function Header({ title = "TowerControl", subtitle = "Task Management", s
     { href: '/kanban', label: 'Kanban' },
     { href: '/daily', label: 'Daily' },
     { href: '/weekly-summary', label: 'Hebdo' },
+    { href: '/weekly-manager', label: 'Manager' },
     ...(isJiraConfigured ? [{ href: '/jira-dashboard', label: `Jira${jiraConfig?.projectKey ? ` (${jiraConfig.projectKey})` : ''}` }] : []),
     { href: '/settings', label: 'Settings' }
   ];