feat(hyprland): swallow GUI windows spawned from foot into the terminal

A viewer opened from a foot shell (zathura/imv, incl. from mc) now hides
the terminal and takes its place, restoring it on close. Requires
standalone foot: server/client mode shares one process across all
windows, so PID-based swallow cannot tell them apart. `$mod+Return` runs
`foot`, not `footclient`, and the `foot --server` exec-once is dropped.

modules/home.nix

@@ -504,6 +504,14 @@ in
       misc = {
         force_default_wallpaper = 0;
         disable_hyprland_logo = true;
+        # Window swallowing: a GUI spawned from a foot shell (e.g. zathura/imv
+        # from mc) hides the terminal and takes its place, restoring it on close.
+        # Matches on the *parent* terminal's class. Needs standalone foot: in
+        # server/client mode all windows share one process, so PID ancestry can't
+        # tell them apart and swallowing breaks — that's why $mod+Return runs
+        # `foot`, not `footclient`.
+        enable_swallow = true;
+        swallow_regex = "^(foot)$";
       };
 
       input = {
@@ -522,7 +530,7 @@ in
       ];
 
       bind = [
-        "$mod,		Return,	exec,		footclient"
+        "$mod,		Return,	exec,		foot"
         "$mod,		q,	killactive"
         "$mod SHIFT,	q,	exit"
         "$mod,		f,	fullscreen,	1"
@@ -563,11 +571,6 @@ in
 
       exec-once = [
         "waybar"
-        # foot in server/daemon mode: $mod+Return runs `footclient`, which
-        # attaches to this one process → faster new-window startup, shared RAM.
-        # Uses foot's default socket, which footclient also defaults to.
-        # Tradeoff: if the server dies, all foot windows die with it.
-        "foot --server"
         # wallpaper (see modules/media.nix): start the awww daemon, then restore
         # the persisted choice. awww keeps no state across restarts, so re-push
         # the ~/.local/share/bg symlink if it exists.