style(ui): simplify panels, remove borders and scrollbars, add padding, enable inline mode

television/cable/opencode-sessions.toml

@@ -18,7 +18,9 @@ layout = "landscape"
 [ui.preview_panel]
 size = 60
 header = "Session: {split:\t:1}"
-border_type = "rounded"
+border_type = "none"
+scrollbar = false
+padding = { left = 2, right = 1, top = 0, bottom = 0 }
 
 [keybindings]
 shortcut = "f4"