本地工具路径DTU_*环境变量改造落地：10处调用点去硬编码+变量优先解析，本机全链路验证通过，文档同步收口，requirements补pre-commit

MDK-ARM/README.md

@@ -58,7 +58,7 @@
 
 ## ⚠️ 注意
 
-- `build.bat` **硬编码本机 Keil 路径** `C:\Keil_v5\UV4\UV4.exe`（换机需改）
+- 工具路径经 `DTU_*` 环境变量解析（`DTU_KEIL_UV4` = UV4.exe 完整路径，`DTU_STLINK_CLI` = ST-LINK_CLI.exe 完整路径；换机设变量即可，**无需改脚本**；契约见 `docs/环境与部署/本地工具路径环境变量方案.md`）
 - 本目录被 pre-commit 门禁**排除**
 - 启动文件的 `Heap_Size = 512B` 是**自研代码禁用 `malloc` 的根因**（见 `AGENTS.md`）
 

MDK-ARM/_build.cmd

@@ -1 +0,0 @@
-@echo off && cd /d "%~dp0" && C:\Keil_v5\UV4\UV4.exe -r "STM32F407-Demo.uvprojx" -t STM32F407-Demo -j0

MDK-ARM/build.bat

@@ -1,11 +1,31 @@
 @echo off
 setlocal
 
-set UV4=C:\Keil_v5\UV4\UV4.exe
 set PROJ=%~dp0STM32F407-Demo.uvprojx
 set LOG=%~dp0build_log.txt
 set TARGET=STM32F407-Demo
 
+:: UV4 location: env var DTU_KEIL_UV4 = full path of UV4.exe.
+:: Required on any MCU build machine; there is NO machine-default fallback
+:: (no C:\Keil_v5 guess). Set it once per machine, user scope (no admin):
+::   [Environment]::SetEnvironmentVariable('DTU_KEIL_UV4', 'D:\Tools\Keil\UV4\UV4.exe', 'User')
+:: then reopen the terminal. Full contract: the DTU_* env var plan document
+:: in docs/ (local tool path env vars plan).
+if defined DTU_KEIL_UV4 goto uv4_set
+echo BUILD_FAIL: environment variable DTU_KEIL_UV4 is not set
+echo Set it to the full path of UV4.exe, e.g.:
+echo   [Environment]::SetEnvironmentVariable('DTU_KEIL_UV4', 'D:\Tools\Keil\UV4\UV4.exe', 'User')
+exit /b 2
+
+:uv4_set
+if exist "%DTU_KEIL_UV4%" goto uv4_ok
+echo ENV_ERROR: DTU_KEIL_UV4 is set but does not exist: "%DTU_KEIL_UV4%"
+echo Fix the variable value. No fallback to another UV4 install is attempted.
+exit /b 2
+
+:uv4_ok
+set UV4=%DTU_KEIL_UV4%
+
 :: UV4 is single-instance: if an IDE process is alive, this -b call may be
 :: forwarded to it (exit code is lost, GUI may open). Warn only; never kill.
 tasklist /fi "imagename eq UV4.exe" /nh | find /i "UV4.exe" >nul

MDK-ARM/download.bat

@@ -1,11 +1,27 @@
 @echo off
 setlocal
 
-set UV4=C:\Keil_v5\UV4\UV4.exe
 set PROJ=%~dp0STM32F407-Demo.uvprojx
 set LOG=%~dp0download_log.txt
 set TARGET=STM32F407-Demo
 
+:: UV4 location: env var DTU_KEIL_UV4 = full path of UV4.exe (same contract
+:: as build.bat; required, no machine-default fallback).
+if defined DTU_KEIL_UV4 goto uv4_set
+echo DOWNLOAD_FAIL: environment variable DTU_KEIL_UV4 is not set
+echo Set it to the full path of UV4.exe, e.g.:
+echo   [Environment]::SetEnvironmentVariable('DTU_KEIL_UV4', 'D:\Tools\Keil\UV4\UV4.exe', 'User')
+exit /b 2
+
+:uv4_set
+if exist "%DTU_KEIL_UV4%" goto uv4_ok
+echo ENV_ERROR: DTU_KEIL_UV4 is set but does not exist: "%DTU_KEIL_UV4%"
+echo Fix the variable value. No fallback to another UV4 install is attempted.
+exit /b 2
+
+:uv4_ok
+set UV4=%DTU_KEIL_UV4%
+
 "%UV4%" -f "%PROJ%" -t%TARGET% -j0 -o "%LOG%"
 
 findstr /C:"Application running" "%LOG%" >nul

MDK-ARM/reset.bat

@@ -1,11 +1,38 @@
 @echo off
 setlocal
 
-set STLINK=C:\Program Files (x86)\STMicroelectronics\STM32 ST-LINK Utility\ST-LINK Utility\ST-LINK_CLI.exe
-if not exist "%STLINK%" (
-    echo RESET_FAIL: ST-LINK_CLI not found at "%STLINK%"
-    exit /b 2
+:: ST-LINK CLI location: env var DTU_STLINK_CLI = full path of ST-LINK_CLI.exe.
+:: Explicit value is used as-is (invalid value = hard error, no silent fallback);
+:: when unset, fall back to PATH (where ST-LINK_CLI.exe).
+set "STLINK="
+if defined DTU_STLINK_CLI goto stlink_check
+where ST-LINK_CLI.exe >nul 2>&1
+if errorlevel 1 goto stlink_missing
+for /f "delims=" %%i in ('where ST-LINK_CLI.exe 2^>nul') do (
+    if not defined STLINK set "STLINK=%%i"
 )
+if not defined STLINK goto stlink_missing
+goto stlink_done
+
+:stlink_check
+if exist "%DTU_STLINK_CLI%" goto stlink_done
+echo ENV_ERROR: DTU_STLINK_CLI is set but does not exist: "%DTU_STLINK_CLI%"
+echo Fix the variable value. No fallback to PATH or other installs is attempted.
+exit /b 2
+
+:stlink_missing
+echo ENV_ERROR: ST-LINK_CLI.exe not found (DTU_STLINK_CLI unset and not on PATH)
+echo Set it to the full path of ST-LINK_CLI.exe, e.g.:
+echo   [Environment]::SetEnvironmentVariable('DTU_STLINK_CLI', 'C:\Tools\STLink\ST-LINK_CLI.exe', 'User')
+exit /b 2
+
+:stlink_done
+if not defined STLINK set "STLINK=%DTU_STLINK_CLI%"
+if exist "%STLINK%" goto stlink_ready
+echo RESET_FAIL: ST-LINK_CLI not found at "%STLINK%"
+exit /b 2
+
+:stlink_ready
 
 if "%~1"=="" goto :reset_run
 if /i "%~1"=="hard" goto :hard