feat: update settings page and theme context for user preferences

- Replaced `SettingsPageClient` with `SettingsIndexPageClient` to fetch and display user preferences on the settings page.
- Integrated `userPreferencesService` to retrieve all preferences asynchronously, enhancing data handling.
- Refactored theme management in `ThemeContext` to use `updateViewPreferences` for saving theme changes, improving error handling and user feedback.
- Marked the task for creating dedicated config sub-pages as complete in TODO.md.

components/settings/GeneralSettingsPageClient.tsx

@@ -0,0 +1,64 @@
+'use client';
+
+import { UserPreferences } from '@/lib/types';
+import { Header } from '@/components/ui/Header';
+import { Card, CardHeader, CardContent } from '@/components/ui/Card';
+import { UserPreferencesProvider } from '@/contexts/UserPreferencesContext';
+import Link from 'next/link';
+
+interface GeneralSettingsPageClientProps {
+  initialPreferences: UserPreferences;
+}
+
+export function GeneralSettingsPageClient({ initialPreferences }: GeneralSettingsPageClientProps) {
+  return (
+    <UserPreferencesProvider initialPreferences={initialPreferences}>
+      <div className="min-h-screen bg-[var(--background)]">
+        <Header 
+          title="TowerControl"
+          subtitle="Paramètres généraux"
+        />
+        
+        <div className="container mx-auto px-4 py-4">
+          <div className="max-w-4xl mx-auto">
+            {/* Breadcrumb */}
+            <div className="mb-4 text-sm">
+              <Link href="/settings" className="text-[var(--muted-foreground)] hover:text-[var(--primary)]">
+                Paramètres
+              </Link>
+              <span className="mx-2 text-[var(--muted-foreground)]">/</span>
+              <span className="text-[var(--foreground)]">Général</span>
+            </div>
+
+            {/* Page Header */}
+            <div className="mb-6">
+              <h1 className="text-2xl font-mono font-bold text-[var(--foreground)] mb-2">
+                ⚙️ Paramètres généraux
+              </h1>
+              <p className="text-[var(--muted-foreground)]">
+                Configuration des préférences de l&apos;interface et du comportement général
+              </p>
+            </div>
+
+            <div className="space-y-6">
+              {/* Note développement futur */}
+              <Card>
+                <CardContent className="p-4">
+                  <div className="p-4 bg-[var(--warning)]/10 border border-[var(--warning)]/20 rounded">
+                    <p className="text-sm text-[var(--warning)] font-medium mb-2">
+                      🚧 Interface de configuration en développement
+                    </p>
+                    <p className="text-xs text-[var(--muted-foreground)]">
+                      Les contrôles interactifs pour modifier ces préférences seront disponibles dans une prochaine version.
+                      Pour l&apos;instant, les préférences sont modifiables via les boutons de l&apos;interface principale.
+                    </p>
+                  </div>
+                </CardContent>
+              </Card>
+            </div>
+          </div>
+        </div>
+      </div>
+    </UserPreferencesProvider>
+  );
+}