Add support for dark mode

[mohamedelhefni]

this PR is addressing the feature requested at #606

Changes

• Migrate to bootstrap v5.3
• Remove custom css that forces light theme
• add toggle theme functionality
  • change editor theme
  • change the data-bs-theme attribute

[sosedoff]

Can you break out bootstrap upgrade into a separate PR? That'll be something we would need to merge first and is definitely easier to check/verify independently from the other changes you're proposing.

[mohamedelhefni]

Hi @sosedoff I have a strong interest in the pgweb project.
Initially, I noticed the absence of vim mode keybindings, which prompted me to contribute to the project. While working on it, I identified an issue related to adding support for a dark theme. Initially, I thought upgrading Bootstrap to v5.3 would seamlessly enable dark theme support, but this process ended up causing complications. The upgrade adversely affected elements like the context menu and dropdown menu, and since the context menu plugins are no longer actively maintained, resolving these issues would take more time than anticipated. Regrettably, I have decided to close this pull request.