feat(themes): add jump-label style for nightfox (#10052)

runtime/themes/nightfox.toml

@@ -34,6 +34,7 @@
 "ui.virtual.whitespace" = { fg = "bg3" } # Whitespace markers in editing area.
 "ui.virtual.indent-guide" = { fg = "black" } # Vertical indent width guides
 "ui.virtual.inlay-hint" = { fg = "comment", bg = "bg2" } # Default style for inlay hints of all kinds
+"ui.virtual.jump-label" = { fg = "blue", modifiers = ["bold"] } # Style for virtual jump labels
 
 "ui.statusline" = { fg = "fg2", bg = "bg0" } # Status line.
 "ui.statusline.inactive" = { fg = "fg3", bg = "bg0" } # Status line in unfocused windows.