feat: add header dependency tracking for programs

programs/src/fetch/Makefile

@@ -84,7 +84,10 @@ $(TARGET): $(OBJDIR)/main.o $(LIBS) $(LINK_LD) Makefile
 
 $(OBJDIR)/main.o: main.cpp Makefile
 	mkdir -p $(OBJDIR)
-	$(CXX) $(CXXFLAGS) -c $< -o $@
+	$(CXX) $(CXXFLAGS) -MMD -MP -c $< -o $@
 
 clean:
 	rm -rf $(OBJDIR) $(TARGET)
+
+# Auto-generated header dependency tracking (-MMD -MP).
+-include $(OBJDIR)/main.d