fix: prevent code-based fallback when useKey is true

[K-Mistele]

Summary

• When useKey: true, the validator now ONLY matches produced keys (event.key) and never falls through to code-based matching (event.code)
• Previously, if the produced key didn't match, the code-based check would still fire — causing hotkeys to trigger based on physical key position even with useKey: true
• This broke non-QWERTY layouts (Dvorak, AZERTY, Colemak) where a single keypress would trigger both the produced-character hotkey AND the physical-key-code hotkey

Test plan

• All 145 existing tests pass
• On Dvorak: pressing physical 'c' (produces 'j') should only trigger 'j' hotkey, not 'c'

🤖 Generated with Claude Code

[github-actions]

Version Bump Summary

Package: @humanlayer/react-hotkeys-hook
Action: bumped to 5.2.6
Reasoning: The change is a pure bug fix — when useKey: true, the validator now exclusively matches against event.key (produced key) without falling through to code-based matching. This corrects broken behavior on non-QWERTY layouts but adds no new API surface and breaks no existing contracts. Patch bump is appropriate.