Use pkg-config flags for nDPI compilation

Let pkg-config provide the correct include paths instead of overriding them.

Dockerfile

@@ -49,13 +49,13 @@ RUN echo "=== Searching for nDPI files ===" && \
     echo "=== Checking pkg-config ===" && \
     pkg-config --cflags libndpi 2>/dev/null || echo "pkg-config failed"
 
-# Fix nDPI compilation with proper linking order and paths
+# Fix nDPI compilation using pkg-config output
 RUN echo "=== Attempting nDPI compilation ===" && \
     ldconfig && \
-    pkg-config --cflags --libs libndpi && \
+    NDPI_FLAGS=$(pkg-config --cflags --libs libndpi) && \
+    echo "Using nDPI flags: $NDPI_FLAGS" && \
     gcc -o protocol_analyzer protocol_analyzer.c \
-        -I/usr/local/include -L/usr/local/lib \
-        -lndpi -lpcap -ljson-c -lpthread -lm \
+        $NDPI_FLAGS -lpcap -ljson-c -lpthread \
     && echo "✅ nDPI compilation successful" \
     || (echo "❌ nDPI compilation failed with exit code $?" && exit 1)