add ESP32 build tools

esp32/Makefile

@@ -0,0 +1,62 @@
+# ========================================================== #
+# Spider Runtime - ESP32 Build System                        #
+# Toolchain: Espressif ESP-IDF (xtensa-esp-elf-g++)          #
+# ========================================================== #
+
+CC          := xtensa-esp-elf-g++
+TARGET      := spider_esp32.elf
+SRCDIR      := ../../src
+BUILDDIR    := bin
+TARGETDIR   := out
+SRCEXT      := cpp
+OBJEXT      := o
+
+ESP_FLAGS   := -DESP32 -DSPIDER_DISTRO_MICRO -DSPIDER_OS_NONE -mlongcalls -ffunction-sections -fdata-sections -fno-exceptions -fno-rtti
+
+# -O0: no optimizations, faster compilation during development
+CFLAGS      := -Wall -std=c++20 -O0 -DSPIDER_COMPILING $(ESP_FLAGS)
+LFLAGS      := -Wl,--gc-sections -mlongcalls
+INC         := -I../../src/
+
+# Exclude desktop-only modules
+EXCLUDE     := $(SRCDIR)/spider/runtime/util/Terminal.cpp \
+               $(SRCDIR)/spider/runtime/debug/LiveDebug.cpp \
+               $(SRCDIR)/spider/SpiderRuntime.cpp
+
+# ESP32 specific entry point (local to this build folder)
+EXTRA       := ./main_esp32.cpp
+
+SOURCES     := $(filter-out $(EXCLUDE), $(shell find $(SRCDIR) -type f -name "*.$(SRCEXT)" 2>/dev/null)) $(EXTRA)
+OBJECTS     := $(patsubst ./%,$(BUILDDIR)/%,$(patsubst $(SRCDIR)/%,$(BUILDDIR)/%,$(SOURCES:.$(SRCEXT)=.$(OBJEXT))))
+
+all: directories $(TARGET)
+	@echo "Build complete: $(TARGETDIR)/$(TARGET)"
+
+remake: cleaner all
+
+directories:
+	@mkdir -p $(TARGETDIR)
+	@mkdir -p $(BUILDDIR)
+
+clean:
+	@$(RM) -rf $(BUILDDIR)
+
+cleaner: clean
+	@$(RM) -rf $(TARGETDIR)
+
+$(TARGET): $(OBJECTS)
+	@echo "Linking $(TARGET)..."
+	$(CC) $(LFLAGS) -o $(TARGETDIR)/$(TARGET) $^
+	@echo "Done!"
+
+$(BUILDDIR)/%.$(OBJEXT): $(SRCDIR)/%.$(SRCEXT)
+	@mkdir -p $(dir $@)
+	@echo "Compiling $<..."
+	$(CC) $(CFLAGS) $(INC) -c -o $@ $<
+
+$(BUILDDIR)/%.$(OBJEXT): ./%.$(SRCEXT)
+	@mkdir -p $(dir $@)
+	@echo "Compiling $<..."
+	$(CC) $(CFLAGS) $(INC) -c -o $@ $<
+
+.PHONY: all remake clean cleaner