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-install.sh

@@ -5,6 +5,10 @@ BPS_RESET=false
 TFT_BUILD=false
 MCU=""
 
+# Constants
+RESET_BAUD=1200
+FIRMWARE_OFFSET=0x00
+
 # Variant groups
 BIGDB_8MB=(
 	"picomputer-s3"
@@ -121,7 +125,7 @@ while [ $# -gt 0 ]; do
 done
 
 if [[ $BPS_RESET == 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
 
@@ -202,7 +206,7 @@ if [ -f "${FILENAME}" ] && [ -n "${FILENAME##*"update"*}" ]; then
 
     echo "Trying to flash ${FILENAME}, but first erasing and writing system information"
     $ESPTOOL_CMD erase-flash
-    $ESPTOOL_CMD write-flash 0x00 "${FILENAME}"
+    $ESPTOOL_CMD write-flash $FIRMWARE_OFFSET "${FILENAME}"
     echo "Trying to flash ${OTAFILE} at offset ${OTA_OFFSET}"
     $ESPTOOL_CMD write-flash $OTA_OFFSET "${OTAFILE}"
     echo "Trying to flash ${SPIFFSFILE}, at offset ${OFFSET}"