Add lab restream pipeline with pirate_drift logo and lib/env.sh.

Encode-once/fanout scripts, HLS output, and single overloadable env source.
Commits assets/pirate_drift.png as default watermark for cluster runs.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/logging.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+log() { printf '[%s] %s\n' "$(date '+%H:%M:%S')" "$*" >&2; }
+warn() { log "WARN: $*"; }
+die() { log "ERROR: $*"; exit 1; }