fix(sway): visible focus ring, floating modifier, volume binds

swayfx: with `border pixel` the visible line is child_border, not `border`
(which only paints title bars). Focused child_border was $base00 = black on
black, i.e. invisible; both are now the same gray.

keybinds: restore `floating_modifier $mod normal` (was `none`) and drop the
`pkill -RTMIN+10 i3blocks` tail from the volume binds -- i3blocks is not in
use, waybar is.

windows: drop a stray trailing semicolon; waybar: remove the unused
sway/submap module.

.config/sway/config.d/windows

@@ -1,5 +1,5 @@
 # Generated windows.
-for_window [title="(?:Open|Save) (?:File|Folder|As)"] floating enable;
+for_window [title="(?:Open|Save) (?:File|Folder|As)"] floating enable
 for_window [title="(?:Open|Save) (?:File|Folder|As)"] resize set 800 600
 for_window [window_role="pop-up"] floating enable
 for_window [window_role="bubble"] floating enable