feat(training): Add next_run.sh to idempotently kick off the next run resuming from the newest final.zip

training/next_run.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env bash
+# The zero-thought kickoff for the training box: pulls latest, names the next
+# run (highest existing runNN + 1), resumes from the newest committed
+# final.zip, and applies the standing flag set below. Idempotent: rerunning
+# while training is live just attaches to the tmux session; rerunning after a
+# finished run starts the next one, continuing from that run's final.zip.
+#
+# Usage: ./next_run.sh [extra train.py args...]
+# Extras are appended after the standing flags, so they win on conflict
+# (e.g. ./next_run.sh --timesteps 5000000, or a fresh start by editing out
+# --resume below for one run).
+set -euo pipefail
+cd "$(dirname "$0")"
+
+# Standing flags for every run. reset-std re-opens exploration each run —
+# we mostly start runs because the reward changed. ent-coef holds it open:
+# run05 lesson — SB3's 0.0001 default let the action std collapse to ~0.1
+# within 4M steps of a resume, re-converging before learning anything new.
+TIMESTEPS=20000000
+N_PARALLEL=14
+SPEEDUP=16
+RESET_STD=0.3
+ENT_COEF=0.001
+
+SESSION="cosmic-train"
+
+# Live session: attach, never start a second trainer or compute a new name.
+if tmux has-session -t "$SESSION" 2>/dev/null; then
+    echo "Session '$SESSION' already running — attaching (detach with Ctrl-B then D)."
+    exec tmux attach -t "$SESSION"
+fi
+
+# Name and resume point come from committed state, so pull before deciding.
+git pull --rebase
+
+LAST=$( { ls -d checkpoints/run[0-9]* logs/run[0-9]* 2>/dev/null || true; } \
+    | sed -E 's|.*run0*([0-9]+).*|\1|' | sort -n | tail -1)
+NEXT=$(printf 'run%02d' $(( ${LAST:-0} + 1 )))
+
+RESUME=$( { ls checkpoints/run[0-9]*/final.zip 2>/dev/null || true; } | sort -V | tail -1)
+
+ARGS=(--timesteps "$TIMESTEPS" --n-parallel "$N_PARALLEL" --speedup "$SPEEDUP" \
+    --reset-std "$RESET_STD" --ent-coef "$ENT_COEF")
+if [ -n "$RESUME" ]; then
+    ARGS+=(--resume "$RESUME")
+    echo "Starting $NEXT, resuming from $RESUME"
+else
+    echo "Starting $NEXT from scratch — no final.zip found in checkpoints/"
+fi
+
+exec ./start_training.sh "$NEXT" "${ARGS[@]}" "$@"