restic scripts: absolute /usr/local/bin/restic — cron PATH lacks it

First cron run (2026-08-28 05:00) failed with 'restic: command not
found'; interactive shells had /usr/local/bin, cron does not.

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

restic-backup.sh

@@ -32,6 +32,7 @@ DB_EXCLUDE_FILE=/root/scripts/plakar-db-exclude   # same opt-out list, same form
 DUMP_DIR=/backup/dumps
 LOCKFILE=/run/lock/restic-backup.lock
 ENVFILE=/root/.restic-env
+RESTIC=/usr/local/bin/restic   # cron PATH lacks /usr/local/bin
 STAGE=all
 
 usage() {
@@ -144,14 +145,14 @@ fi  # stage dumps
 if [ "$STAGE" = all ] || [ "$STAGE" = backup ]; then
 
 log "restic backup -> $REPO"
-restic -r "$REPO" backup \
+$RESTIC -r "$REPO" backup \
     --pack-size 64 --read-concurrency 8 -o s3.connections=8 \
     --exclude-file "$EXCLUDE_FILE" \
     --files-from-verbatim "$PATHS_FILE" "$DUMP_DIR" \
     || { echo "restic backup failed" >&2; rc=1; }
 
 log "forget: keep 14d/8w/6m"
-restic -r "$REPO" forget --group-by host \
+$RESTIC -r "$REPO" forget --group-by host \
     --keep-daily 14 --keep-weekly 8 --keep-monthly 6 || rc=1
 
 fi  # stage backup