Update Dockerfile

Dockerfile

@@ -39,9 +39,9 @@ RUN wget -q https://tests.stockfishchess.org/api/nn/nn-9a0cc2a62c52.nnue && \
 
 # Build from the detected 'src/' folder - ARCH=x86-64 is the official "Portable" build
 RUN make -j$(nproc) all ARCH=x86-64 && \
-    mkdir -p /app/engine_bin && \
-    cp stockfish /app/engine_bin/deepcastle && \
-    chmod +x /app/engine_bin/deepcastle
+    mkdir -p /app/engine && \
+    cp stockfish /app/engine/deepcastle && \
+    chmod +x /app/engine/deepcastle
 
 # ============================================================
 # LAUNCHER PREPARATION (The Search & Destroy Fix)