chore(gate): every lane reports how long it took, and a run can log the times for comparison

scripts/check.sh

@@ -9,6 +9,8 @@
 #   bash scripts/check.sh lint   the static lanes only: no tests, no build, no audits
 #   … --brief                    (either mode) a lane's output only when it fails, and only its first
 #                                error lines — for an agent, whose context the full log would flood
+#   GATE_TIMES_FILE=<file> …     also append each lane's time as a TSV row (UTC, mode, lane, seconds,
+#                                ok|red, HEAD's tree) — to compare runs; every run prints the times anyway
 #
 # Each lane runs even when an earlier one failed, and the summary names every red one: a gate that
 # stops at the first failure hides the second until the first is fixed. The backend lanes run in the
@@ -29,21 +31,42 @@ done
 export MSYS_NO_PATHCONV=1 # Git Bash: do not rewrite the in-container paths below
 TESTCOMPOSE=backend/docker-compose.test.yml
 failed=()
+timings=()
+ms() { date +%s%3N; }
+secs() { awk -v t="$1" 'BEGIN { printf "%.1f", t / 1000 }'; }
+# How long each lane took: a line after the lane, a table at the end, and — when GATE_TIMES_FILE names a
+# file — one tab-separated row per lane appended to it (UTC time, mode, lane, seconds, ok|red, tree), so
+# runs can be compared. The script writes no file unless asked to.
+took=""
+timed() { # timed <name> <ok|red> <start-ms> — sets $took (no subshell: it must add to $timings)
+  took="$(secs $(($(ms) - $3)))"
+  timings+=("$(printf '%8s s  %s' "$took" "$1")$([ "$2" = red ] && echo '  (red)')")
+  if [ -n "${GATE_TIMES_FILE:-}" ]; then
+    printf '%s\t%s\t%s\t%s\t%s\t%s\n' "$(date -u +%FT%TZ)" "$mode" "$1" "$took" "$2" \
+      "$(git rev-parse --short 'HEAD^{tree}' 2>/dev/null)" >>"$GATE_TIMES_FILE"
+  fi
+  return 0
+}
 lane() { # lane <name> <command…> — run it, remember a failure, never stop
-  local name="$1"
+  local name="$1" t0 result=ok
   shift
+  t0="$(ms)"
   if [ "$brief" = 0 ]; then
     echo ">> $name…"
-    "$@" || failed+=("$name")
+    "$@" || { failed+=("$name"); result=red; }
+    timed "$name" "$result" "$t0"
+    echo "<< $name: $took s"
     return 0
   fi
   local out
   out="$(mktemp)"
   if "$@" >"$out" 2>&1; then
-    echo ">> $name: ok"
+    timed "$name" ok "$t0"
+    echo ">> $name: ok ($took s)"
   else
     failed+=("$name")
-    echo ">> $name: FAILED"
+    timed "$name" red "$t0"
+    echo ">> $name: FAILED ($took s)"
     brief_excerpt "$out"
   fi
   rm -f "$out"
@@ -102,6 +125,7 @@ basedpyright() {
 
 frontend() { (cd frontend && "$@"); }
 
+gate_t0="$(ms)"
 lane "ruff" ruff_check
 lane "ruff format --check" ruff_format
 lane "basedpyright (new errors only)" basedpyright
@@ -139,6 +163,9 @@ if [ "$mode" = all ]; then
   lane "npm audit (production dependencies)" frontend npm audit --omit=dev --audit-level=high
 fi
 
+echo ">> lane times:"
+printf '%s\n' "${timings[@]}"
+echo "$(printf '%8s' "$(secs $(($(ms) - gate_t0)))") s  total"
 if [ ${#failed[@]} -eq 0 ]; then
   echo ">> gate ($mode): green ✓"
   exit 0