Initial commit: swipe-to-zoom touchscreen navigation for socktop

Tiled socktop dashboard where a right-to-left swipe zooms into each host
full-screen and left-to-right walks back out.

The carousel is tmux pane zoom rather than separate socktop instances, so
there is one process per host: half the processes, no reconnect delay when
swiping back, and constant polling load on the monitored hosts.

Gestures come from lisgd because libinput emits gesture events only for
touchpads, never touchscreens, which rules out libinput-gestures entirely.

Documents the four gotchas found while building this: panels reporting 2-3
contacts for a one-finger swipe, X needing to ignore the panel so the
terminal and socktop stop competing for the same touches, tmux mouse mode
being incompatible with swipes, and lisgd not grabbing the device
exclusively so two instances double-fire.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

socktop-rack

@@ -0,0 +1,47 @@
+#!/bin/sh
+# Build the socktop display session: one window, N tiled panes, one per host.
+# Pane index order is the swipe order.
+set -eu
+
+# shellcheck source=config.env
+for c in /usr/local/etc/socktop-swipe.env "$(dirname "$0")/config.env"; do
+	[ -r "$c" ] && . "$c" && break
+done
+
+: "${SOCKTOP_HOSTS:?no SOCKTOP_HOSTS -- is the config installed?}"
+: "${SOCKTOP_SESSION:=socktop4}"
+: "${SOCKTOP_BIN:=socktop}"
+
+WIN="$SOCKTOP_SESSION:rack"
+
+tmux kill-session -t "$SOCKTOP_SESSION" 2>/dev/null || true
+
+first=1
+for h in $SOCKTOP_HOSTS; do
+	if [ "$first" = 1 ]; then
+		tmux new-session -d -s "$SOCKTOP_SESSION" -n rack "$SOCKTOP_BIN -P $h"
+		first=0
+	else
+		# Split the most recently created pane so creation order == index order.
+		tmux split-window -t "$WIN" "$SOCKTOP_BIN -P $h"
+	fi
+	# Label the pane with the host it is showing.
+	tmux select-pane -t "$WIN.$(tmux display-message -t "$WIN" -p '#{pane_index}')" -T "$h"
+done
+
+tmux select-layout -t "$WIN" tiled
+tmux select-pane -t "$WIN.0"
+
+tmux set-option -t "$SOCKTOP_SESSION" pane-border-status top
+tmux set-option -t "$SOCKTOP_SESSION" pane-border-format ' #{pane_title} '
+tmux set-option -t "$SOCKTOP_SESSION" status off
+
+# Keep dead panes so pane indices stay stable if a socktop exits.
+tmux set-option -t "$SOCKTOP_SESSION" remain-on-exit on
+
+# Mouse mode MUST stay off. With it on, every touch swipe is ALSO delivered to
+# tmux as a click-drag: dragging across a pane border resizes it and taps
+# reselect panes, which fights the gesture daemon. See README, "Why no tapping".
+tmux set-option -t "$SOCKTOP_SESSION" mouse off
+
+exec tmux attach -t "$SOCKTOP_SESSION"