autoresearch: temp sweep, engine evidence, env overlays, arms driver

Four harness gaps that block an honest MTP re-measurement:

- measure: AR_TEMPS sweeps sampling temperatures (default "0,0.7"). Draft
  ACCEPTANCE is sampling-dependent — a greedy draft matches a greedy target
  exactly and is rejected more under a non-greedy target — so judging a spec
  arm only at temperature 0 judges half the contract. The unsuffixed keys stay
  temperature 0, so every historical number remains comparable.
- window: capture an evidence.log sidecar (expert-plan lines, compile path,
  graph sizes, /metrics spec-decode and cache counters, OOM signatures). The
  arena/overhead/reserve numbers exist ONLY in the boot log; an arm that loses
  decode speed is otherwise unexplainable afterwards.
- orchestrator: FRANK_PRIMARY_AR_ENV_FILE stages an env other than the repo's,
  which is how arms A/B without mutating the checkout (the fingerprint covers
  whatever is staged, so the memo can never answer one arm with another's
  numbers), plus METRIC lines for the swept temperatures and the evidence dump.
- scripts/autoresearch/frank-primary-arms.sh: runs a sequence of full windows
  (baseline, MTP3+probabilistic with a step-4 capture ladder at precise memory
  ON, the same at the default overhead, and the vendor SEQS-16 shape), gating
  each staged env on its JSON knobs still parsing AFTER sourcing — an unquoted
  {"temperature":0.7} loses its quotes at source time and reaches the engine as
  {temperature:0.7}, which is a 20-minute boot wasted.

autoresearch.sh

@@ -29,7 +29,10 @@ SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
 HOST="${FRANK_PRIMARY_AR_HOST:-dankserver}"
 STAGE="/home/dank/.autoresearch-frank-primary"
 
-ENV_FILE="$SCRIPT_DIR/scripts/frank-primary.env"
+# FRANK_PRIMARY_AR_ENV_FILE stages a DIFFERENT env than the repo's — that is how
+# the arms driver A/Bs engine knobs without mutating the checkout. The
+# fingerprint covers whatever file is staged, so the memo cannot cross arms.
+ENV_FILE="${FRANK_PRIMARY_AR_ENV_FILE:-$SCRIPT_DIR/scripts/frank-primary.env}"
 SERVE="$SCRIPT_DIR/scripts/serve-frank-primary.sh"
 UNIT="$SCRIPT_DIR/scripts/frank-primary.service"
 MEASURE="$SCRIPT_DIR/scripts/autoresearch/frank-primary-measure.py"
@@ -58,6 +61,13 @@ print("METRIC ttft_ms_4096=%s" % m["ttft_ms_4096"])
 print("METRIC kv_tokens=%s" % (run.get("kv_tokens") or 0))
 print("METRIC boot_seconds=%s" % (run.get("boot_seconds") or -1))
 print("METRIC completion_tokens_4096=%s" % m.get("completion_tokens_4096", 0))
+# Any extra sampling temperature the measure swept (AR_TEMPS), e.g. the 0.7
+# arm — that is where speculative-decode acceptance shows up, since a greedy
+# draft matches a greedy target exactly and is rejected more under real
+# sampling. Suffixed keys only (_t0.7), so the historical lines are untouched.
+for k in sorted(m):
+    if "_t" in k and (k.startswith("decode_tps") or k.startswith("ttft_ms")):
+        print("METRIC %s=%s" % (k, m[k]))
 ' "$1"
 }
 
@@ -101,4 +111,7 @@ run_json="$(ssh_run "cat '$STAGE/run.json'")" || {
 echo "[autoresearch] window result:" >&2
 printf '%s\n' "$run_json" >&2
 emit_metrics "$run_json"
+
+echo "[autoresearch] engine evidence (plan / compile path / spec counters):" >&2
+ssh_run "cat '$STAGE/evidence.log' 2>/dev/null" >&2 || true
 exit 0