Move pathfinders to dedicated files

cpp/Makefile

@@ -2,7 +2,7 @@
 # Generated by Kimi K2
 #---------- configurable ----------
 CXX      := g++
-CXXFLAGS := -std=c++23 -Wall -Wextra -Wpedantic -ggdb3
+CXXFLAGS := -Isrc -std=c++23 -Wall -Wextra -Wpedantic -ggdb3
 LDFLAGS  :=
 LDLIBS   := -lSDL3 -lSDL3_image -lGLEW -lGL
 
@@ -11,7 +11,7 @@ BUILD_DIR:= build
 TARGET   := pathfinding
 
 #----------------------------------
-SOURCES := $(wildcard $(SRC_DIR)/*.cpp)
+SOURCES := $(shell find $(SRC_DIR) -name '*.cpp')
 OBJECTS := $(SOURCES:$(SRC_DIR)/%.cpp=$(BUILD_DIR)/%.o)
 
 #----------------------------------
@@ -25,6 +25,7 @@ $(TARGET): $(OBJECTS)
 
 # compile step
 $(BUILD_DIR)/%.o: $(SRC_DIR)/%.cpp | $(BUILD_DIR)
+	@mkdir -p $(dir $@)
 	$(CXX) $(CXXFLAGS) -c -o $@ $<
 
 $(BUILD_DIR):