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.

scripts/autoresearch/frank-primary-window.sh

@@ -118,7 +118,7 @@ main() {
         [ -f "$STAGE/$f" ] || { log "staged file missing: $STAGE/$f"; exit 1; }
     done
     mkdir -p "$STAGE/last"
-    rm -f "$STAGE/run.json" "$STAGE/fail.log" "$STAGE/measure.out"
+    rm -f "$STAGE/run.json" "$STAGE/fail.log" "$STAGE/measure.out" "$STAGE/evidence.log"
 
     local t_start t0 i kvline kv_tokens kv_conc measure_json boot_seconds
     t_start="$(date +%s)"
@@ -177,6 +177,24 @@ main() {
     kv_tokens="$(printf '%s' "$kvline" | sed -E 's/.*GPU KV cache size: ([0-9,]+) tokens.*/\1/' | tr -d ',' || true)"
     kv_conc="$(printf '%s' "$kvline" | sed -E 's/.*per request: ([0-9.]+x).*/\1/' || true)"
 
+    # Human-facing evidence, in a sidecar file because it is multi-line prose,
+    # not metrics: the expert-plan lines (the ONLY place the arena / runtime
+    # overhead / KV-reserve numbers exist — they are never in /metrics), the
+    # compile path (cold build vs cache hit), the graph-capture sizes, the
+    # speculative-decode counters, and any OOM signature. Without this an arm
+    # that loses decode speed is unexplainable afterwards.
+    {
+        echo "=== engine plan / capacity / spec evidence ==="
+        podman logs "$CTR" 2>&1 | grep -E \
+'KV cache size|Maximum concurrency|layers split|expert cache|runtime overhead|non-default args|r4d all-reduce|Using \[|cudagraph|CUDA graph|Capturing|graph for compile range|torch.compile took|Directly load the compiled|speculative|Speculative|acceptance|Acceptance|offload|precise|OutOfMemory|Tried to allocate|Engine core initialization failed' \
+            | tail -150 || true
+        echo "=== /metrics counters (spec decode, caches, success) ==="
+        curl -s --max-time 15 http://127.0.0.1:7770/metrics 2>/dev/null \
+            | grep -E '^vllm:(spec_decode|gpu_cache|prefix_cache|request_success|generation_tokens|iteration)' \
+            | head -80 || true
+    } >"$STAGE/evidence.log" 2>&1 || true
+    log "engine evidence -> $STAGE/evidence.log ($(wc -l <"$STAGE/evidence.log") lines)"
+
     measure_json="$(grep -E '^\{' "$STAGE/measure.out" | tail -1 || true)"
     if [ -z "$measure_json" ]; then
         log "measure produced no JSON result line"