fix: increase input border contrast for better visibility Light: 91.4% → 80% lightness; Dark: 17.5% → 28% lightness Addresses WCAG AA non-text contrast requirements for input boundaries Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent) Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

fix: increase input border contrast for better visibility Light: 91.4% → 80% lightness; Dark: 17.5% → 28% lightness Addresses WCAG AA non-text contrast requirements for input boundaries Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent) Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai> #325