Add tests for checking:
- environment variable override with hex values
- invalid environment variable handling
- Kconfig-default behavior with device detection
- precedence rules (environment overrides device detection)
- serial terminal detection by manipulating sandbox state
Also expose calc_check_console_lines() in console.h for testing
and update pager functionality to use bypass mode when serial
is not connected to a terminal.
Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
