Dark mode proper + revert change #179

Hello,

Reversion of update #179 completed (revert most of).
Theme support, it has been integrated, with a selection of themes compatible with the dark CPI Extension.
Implementation of a new feature for color themes, including a reset option and color limiter for consistent contrast across all scenarios.
The 'last visited' bug has been addressed and fixed.

@dbeck121, we are ready for release... Addressed all the known issue as discussed.

Please report any issues encountered with these updates. Thank you.

dbeck121 / CPI-Helper-Chrome-Extension