fix: evolve.sh does not write \note\ field — schema drift between hand-written and evolved entries (#719)

- Pass seed basename into the admission Python block as argv[7]
- Add \`note\` field to every new evolved entry: "Evolved from <seed> (run<N> gen<G>)"
- Add migration comment noting entries admitted before this fix may have note: null

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

tools/push3-evolution/evolve.sh

@@ -752,6 +752,9 @@ log "========================================================"
 
 log ""
 log "=== Seed pool admission (run=$RUN_ID, threshold=$ADMISSION_THRESHOLD) ==="
+# NOTE: entries admitted before fix #719 (2026-03-15) may have note: null.
+# All entries admitted by this script from this point forward carry an
+# auto-generated note of the form "Evolved from <seed> (run<N> gen<G>)".
 
 mkdir -p "$SEEDS_DIR"
 
@@ -760,6 +763,7 @@ _ADMISSION_RC=0
 
 python3 - "$OUTPUT_DIR" "$WORK_DIR" "$SEEDS_DIR" \
   "$ADMISSION_THRESHOLD" "$RUN_ID" "$(date -u '+%Y-%m-%d')" \
+  "$(basename "$SEED")" \
   > "$_ADMISSION_OUT" 2>&1 <<'PYEOF' || _ADMISSION_RC=$?
 import json, sys, os, hashlib, shutil, tempfile
 
@@ -767,6 +771,7 @@ output_dir, work_dir, seeds_dir = sys.argv[1], sys.argv[2], sys.argv[3]
 threshold  = int(sys.argv[4])
 run_id     = sys.argv[5]
 today      = sys.argv[6]
+seed_name  = sys.argv[7]
 MAX_EVOLVED = 100  # cap applies to evolved entries only; hand-written are always pinned
 
 manifest_path = os.path.join(seeds_dir, 'manifest.jsonl')
@@ -860,6 +865,7 @@ for fitness, push3_path, gen_idx, cand_str in qualifying:
         'run':        run_id,
         'generation': gen_idx,
         'date':       today,
+        'note':       f'Evolved from {seed_name} (run{run_id} gen{gen_idx})',
     }
     new_items.append((fitness, push3_path, entry))