fix: enable KCEF support in Docker and fix init race condition

Add KCEF build args to docker-compose.yml so the image is built with
Xvfb and CEF binaries, enabling WebView-based sources like MangaFire.

Remove redundant kcefDir.createDirectories() in ServerSetup which caused
FileAlreadyExistsException when KCEF.init tried to create the same dir.

docker-compose.yml

@@ -1,7 +1,12 @@
 ---
 services:
   suwayomi:
-    build: .
+    build:
+      context: .
+      args:
+        TACHIDESK_KCEF: "y"
+        TARGETPLATFORM: linux/amd64
+        TACHIDESK_KCEF_RELEASE_URL: https://api.github.com/repos/DatL4g/KCEF/releases/latest
     platform: linux/amd64
     image: registry.achmad.dev/suwayomi-server:latest
     # user: 1000:1000