Kaia Counter Test v0.5.6 — supporter number / pre-issue copy

Source:
- Created from v0.5.5.
- v0.5.5 predecessor remains untouched.

UI changes:
- Counter label: YOUR SUPPORTER'S NUMBER
- Number display remains 8 cells; pre-issue mask remains KaiaSpec.
- GET NUMBER remains below the display.
- Added explanatory copy below the button:
  One number is issued per donation.

Counter/cooldown/issuance logic unchanged.
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