Fix esptool detection and baud rate issues in Windows batch scripts (#7856)

- Fix esptool detection to use 'version' subcommand instead of no arguments
- Fix device-update.bat to use 115200 bps for flashing, 1200 bps only for reset
- Add missing closing quotes in debug messages

Replace magic numbers with named constants for better maintainability

- Add RESET_BAUD=1200 constant for reset baud rate
- Add UPDATE_OFFSET=0x10000 constant for update flash offset
- Use constants instead of hardcoded values throughout script

Extract magic numbers to constants in shell scripts for consistency

- Add FLASH_BAUD, RESET_BAUD, UPDATE_OFFSET constants to device-update.sh
- Add RESET_BAUD, FIRMWARE_OFFSET constants to device-install.sh
- Replace hardcoded values with named constants throughout
- Maintain consistency with batch script improvements

Fix Python path quoting and remove unreachable code

- Quote Python interpreter paths to handle spaces in paths like 'C:\Program Files\Python\python.exe'
- Remove unreachable GOTO statements after EXIT /B commands
- Improve robustness when custom Python interpreters are specified

Fix esptool detection for pipx installations

- Change from checking ERRORLEVEL GEQ 2 to EQU 9009
- Pipx-installed esptool returns exit code 2 when showing help (normal)
- Only treat Windows 'command not found' error (9009) as truly not found
- Add debug output to show actual exit codes for troubleshooting

bin/device-update.sh

@@ -3,6 +3,11 @@
 PYTHON=${PYTHON:-$(which python3 python|head -n 1)}
 CHANGE_MODE=false
 
+# Constants
+FLASH_BAUD=115200
+RESET_BAUD=1200
+UPDATE_OFFSET=0x10000
+
 # Determine the correct esptool command to use
 if "$PYTHON" -m esptool version >/dev/null 2>&1; then
     ESPTOOL_CMD="$PYTHON -m esptool"
@@ -64,7 +69,7 @@ done
 shift "$((OPTIND-1))"
 
 if [ "$CHANGE_MODE" = true ]; then
-	$ESPTOOL_CMD --baud 1200 --after no_reset read_flash_status
+	$ESPTOOL_CMD --baud $RESET_BAUD --after no_reset read_flash_status
     exit 0
 fi
 
@@ -75,7 +80,7 @@ fi
 
 if [ -f "${FILENAME}" ] && [ -z "${FILENAME##*"update"*}" ]; then
     echo "Trying to flash update ${FILENAME}"
-    $ESPTOOL_CMD --baud 115200 write-flash 0x10000 "${FILENAME}"
+    $ESPTOOL_CMD --baud $FLASH_BAUD write-flash $UPDATE_OFFSET "${FILENAME}"
 else
     show_help
     echo "Invalid file: ${FILENAME}"