Code modernization + Countdown to close#3

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rinc3w1nd wants to merge 3 commits intoUnallocated:masterfrom

rinc3w1nd:master

Commits on Feb 23, 2026

Modernize codebase: switch to gpiozero, fix bugs, add logging and validation
rinc3w1nd
committed
Add closing countdown feature with keyholder authentication

rinc3w1nd
and
claude
committed
Add PIN-based keyholder auth, system lockout, and dark modern dashboard

rinc3w1nd
and
claude
committed