refactor: modernize vial examples

Modernize all the Vial example keyboards/keymaps.

QMK is slowly moving toward failing compilation when things that should be configured in info.json aren't; see PR 23449.
USB_POLLING_INTERVAL_MS has been 1 by default since early 2022.
CORTEX_ENABLE_WFI_IDLE has been TRUE for ChibiOS builds by default since late 2023.
Hardcoded transparent layers are no longer required.
Locking switches are not nearly common enough to justify on-by-default configuration.

vial-kb / vial-qmk