Kaia Counter v0.5.3 — cooldown UI fix

- The issued visitor's button is disabled only while the configured cooldown is active.
- After cooldown expires, the button becomes GET NUMBER again.
- During cooldown, the visitor's own issued number remains displayed.
- Before any issue, display is KaiaSpec + GET NUMBER.
- Existing counter/history data is preserved.
- Plugin identity preserved: kaia-counter-test/kaia-counter-test.php
