Based on the official 3CX T5x template, stripped to T58W-only with the
door unlock URL hardcoded on line key 2 (type 17/URL). Keys 3+ remain
managed by 3CX BLF as usual.
- Backlight dims to level 1 after 5 min, never fully sleeps
- Screensaver and power saving disabled
- README updated with T54W references and SP template manual steps
Two variants:
- yealinkT54W-door-unlock.ph.xml — line key 2 as door unlock URL
- yealinkT54W-door-unlock-with-sp.ph.xml — line key 2 as door unlock, keys 3-5 as shared parking SP1-3