refactor: 工程清理，打造基础模板

- 删除冗余文件：main_backup/main_minimal/main_full、GD32F4xx_AddOn_Temp/、GD32F4xx_Custom_Backup/、GD32F4xx_Official/
- 删除无关工具：read_pdf.py、openocd_test.txt、version.txt
- 重构 main.cpp：去除 STEP 机制，简化为线性启动流程
- 清理 CMakeLists.txt：移除 usart0.c 引用、死代码、冗余 REMOVE_ITEM
- 修正 config.h SystemCoreClock 为 168MHz
- 修复 gd32f4xx_it.cpp 中已删除的 main.h 引用

CMakeLists.txt

@@ -64,7 +64,6 @@ include_directories(
     libs/common
     libs/CMSIS
     libs/thirdparty
-    libs/thirdparty/GD32F4xx_Official/LCD_TOUCH_MCU_LiangShanPi/Hardware/usart0
 )
 
 if(GD32F4XX_LIB_FOUND)
@@ -81,7 +80,6 @@ endif()
 # Application sources (both .c and .cpp)
 file(GLOB_RECURSE APP_SOURCES
     app/*.cpp
-    app/tasks/*.cpp
     bsp/*.cpp
     drv/adc/*.cpp
     drv/i2c/*.cpp
@@ -100,13 +98,6 @@ file(GLOB_RECURSE APP_SOURCES
     bsp/device/flash/*.cpp
 )
 
-# Remove backup/extra main files from app sources
-list(REMOVE_ITEM APP_SOURCES
-    ${CMAKE_SOURCE_DIR}/app/main_backup.c
-    ${CMAKE_SOURCE_DIR}/app/main_minimal.c
-    ${CMAKE_SOURCE_DIR}/app/main_full.cpp
-)
-
 
 
 # GD32 standard peripheral library sources
@@ -119,13 +110,8 @@ set(ASSEMBLY_SOURCES
     ${CMAKE_SOURCE_DIR}/libs/thirdparty/GD32F4xx/Startup/startup_gd32f450_470.S
 )
 
-# Additional serial port driver
-set(USART0_SOURCE
-    ${CMAKE_SOURCE_DIR}/libs/thirdparty/GD32F4xx_Official/LCD_TOUCH_MCU_LiangShanPi/Hardware/usart0/usart0.c
-)
-
 # Combine all sources
-set(ALL_SOURCES ${APP_SOURCES} ${GD32_SOURCES} ${ASSEMBLY_SOURCES} ${USART0_SOURCE})
+set(ALL_SOURCES ${APP_SOURCES} ${GD32_SOURCES} ${ASSEMBLY_SOURCES})
 
 add_executable(${PROJECT_NAME} ${ALL_SOURCES})
 
@@ -148,13 +134,6 @@ add_custom_command(TARGET ${PROJECT_NAME} POST_BUILD
 set(FLASH_TOOL "auto" CACHE STRING "Programming tool to use (openocd, jlink, pyocd, auto)")
 set_property(CACHE FLASH_TOOL PROPERTY STRINGS "openocd" "jlink" "pyocd" "auto")
 
-# Check if flash script exists
-if(NOT EXISTS ${CMAKE_SOURCE_DIR}/tools/flash.py)
-    message(WARNING "Flash script not found: ${CMAKE_SOURCE_DIR}/tools/flash.py")
-    message(STATUS "Creating default flash script...")
-    # Optionally create the flash script here or just warn
-endif()
-
 # Custom target for flashing
 add_custom_target(flash
     DEPENDS ${PROJECT_NAME}