Complete OWE service setup and lock feed fallback

shell/plugins/lock/poster.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# One cached frame shared by all lock outputs, including when OWE is paused.
+set -euo pipefail
+
+source_path=$1
+cache_dir="${XDG_CACHE_HOME:-$HOME/.cache}/omarchy/lock-poster"
+signature=$(stat -Lc '%s:%y:%z' "$source_path")
+key=$(printf '%s\n%s' "$source_path" "$signature" | sha256sum | cut -d ' ' -f 1)
+poster="$cache_dir/poster-$key.jpg"
+mkdir -p "$cache_dir"
+exec {lock_fd}>"$cache_dir/.lock"
+flock -w 10 "$lock_fd"
+
+if [[ ! -s $poster ]]; then
+  temporary=$(mktemp "$cache_dir/.poster-XXXXXX.jpg")
+  trap 'rm -f "$temporary"' EXIT
+  timeout -k 1 5 ffmpegthumbnailer -i "$source_path" -o "$temporary" -s 1920 -q 8 {lock_fd}>&-
+  [[ -s $temporary ]]
+  mv -f "$temporary" "$poster"
+  find "$cache_dir" -maxdepth 1 -type f -name 'poster-*.jpg' ! -name "poster-$key.jpg" -delete
+fi
+
+printf '%s\n' "$poster"