scripts: use $0 for cmd name in q, sched, sh

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/b/q

@@ -16,4 +16,8 @@ Flags:
   -help             show this help
 EOF
 done
+cmd=${0##*/}
+if [ $# -eq 0 ] && [ -t 0 ]; then
+    printf '%s: prompt required: pass as arguments or pipe via stdin\n' "$cmd" >&2; exit 1
+fi
 exec "${0%/*}/../s/job" "$@"

scripts/b/sched

@@ -16,6 +16,10 @@ Flags:
   -help             show this help
 EOF
 done
+cmd=${0##*/}
+if [ $# -eq 0 ] && [ -t 0 ]; then
+    printf '%s: prompt required: pass as arguments or pipe via stdin\n' "$cmd" >&2; exit 1
+fi
 OLLIE=${OLLIE:-$HOME/mnt/ollie}
 "${0%/*}/../s/job" -bg "$@" | while IFS= read -r id; do
     [ -n "$id" ] && printf '%s/b/%s\n' "$OLLIE" "$id"

scripts/s/sh

@@ -20,6 +20,7 @@ save_session() {
     mv "$tmp" "$LAST"
 }
 
+cmd=${0##*/}
 die()     { printf 'error: %s\n' "$*" >&2; exit 1; }
 is_idle() { [ "$(tr -d '[:space:]' < "$S/state" 2>/dev/null)" = "idle" ]; }
 drain() {
@@ -30,8 +31,8 @@ drain() {
 }
 
 usage() {
-    cat <<'EOF'
-usage: osh [flags]
+    cat <<EOF
+usage: $cmd [flags]
 
 Flags:
   -new              always create a new session