[idea] Option to set the focused pane border style (thick vs plain)

[asumaran]

idea / problem

The focused pane uses a thick border, and there’s currently no way to adjust its thickness. The only configurable option is the accent color.

requested change

Add [ui] active_pane_border with "thick" (default) and "plain". "plain" keeps the accent color but uses the regular border glyphs.

I already implemented this and accidentally opened a PR before starting a discussion. The PR was automatically closed by the repository’s bot, as discussions are required before feature PRs can be considered.

Below is a comparison of the two styles. The top image shows my branch, and the bottom image shows the current behavior.

why you want this

The thick border feels heavy in multi-pane layouts; accent color alone is enough to mark the active pane and looks cleaner. Default stays "thick" for everyone else.

[asumaran]

This was already addressed in 4421c0f. I didn’t notice it because I was using the Homebrew version of Herdr. I’m now using the version installed via https://herdr.dev/install.sh, and the thick border around the active pane is gone. Closing.