refactor: convert favorites to Server Actions

- Add src/app/actions/favorites.ts with addToFavorites and removeFromFavorites
- Update SeriesHeader to use Server Actions instead of fetch
- Keep API route GET only (POST/DELETE removed)

src/app/api/komga/favorites/route.ts

@@ -4,9 +4,9 @@ import { SeriesService } from "@/lib/services/series.service";
 import { ERROR_CODES } from "@/constants/errorCodes";
 import { AppError } from "@/utils/errors";
 import { getErrorMessage } from "@/utils/errors";
-import type { NextRequest } from "next/server";
 import logger from "@/lib/logger";
 
+// GET reste utilisé par Sidebar et SeriesHeader pour récupérer la liste des favoris
 export async function GET() {
   try {
     const favoriteIds: string[] = await FavoriteService.getAllFavoriteIds();
@@ -61,67 +61,3 @@ export async function GET() {
     );
   }
 }
-
-export async function POST(request: NextRequest) {
-  try {
-    const { seriesId }: { seriesId: string } = await request.json();
-    await FavoriteService.addToFavorites(seriesId);
-    return NextResponse.json({ message: "⭐️ Série ajoutée aux favoris" });
-  } catch (error) {
-    logger.error({ err: error }, "Erreur lors de l'ajout du favori:");
-    if (error instanceof AppError) {
-      return NextResponse.json(
-        {
-          error: {
-            code: error.code,
-            name: "Favorite add error",
-            message: getErrorMessage(error.code),
-          },
-        },
-        { status: 500 }
-      );
-    }
-    return NextResponse.json(
-      {
-        error: {
-          code: ERROR_CODES.FAVORITE.ADD_ERROR,
-          name: "Favorite add error",
-          message: getErrorMessage(ERROR_CODES.FAVORITE.ADD_ERROR),
-        },
-      },
-      { status: 500 }
-    );
-  }
-}
-
-export async function DELETE(request: NextRequest) {
-  try {
-    const { seriesId }: { seriesId: string } = await request.json();
-    await FavoriteService.removeFromFavorites(seriesId);
-    return NextResponse.json({ message: "💔 Série retirée des favoris" });
-  } catch (error) {
-    logger.error({ err: error }, "Erreur lors de la suppression du favori:");
-    if (error instanceof AppError) {
-      return NextResponse.json(
-        {
-          error: {
-            code: error.code,
-            name: "Favorite delete error",
-            message: getErrorMessage(error.code),
-          },
-        },
-        { status: 500 }
-      );
-    }
-    return NextResponse.json(
-      {
-        error: {
-          code: ERROR_CODES.FAVORITE.DELETE_ERROR,
-          name: "Favorite delete error",
-          message: getErrorMessage(ERROR_CODES.FAVORITE.DELETE_ERROR),
-        },
-      },
-      { status: 500 }
-    );
-  }
-}