port: add check-all; verify-screen ignored its own statistic; 'six expected DIFFERS' was wrong

Eleven tools and nothing ran them together -- the ninth instance of correct,
documented and unexercised, one level up. check-all runs the four that assert,
reports the oracle table, and gives verify-screen an allowance that EXPIRES when
the pin lands rather than standing forever. All eleven exercised first; none had
rotted.

verify-screen computed over3 because 'a single max cannot tell 2 pixels from
25 444' and then decided the verdict on max alone: main_menu (max 4, over3 0)
read DIFFERS while extras (max 3, over3 0) read OK. The bar is unchanged; a frame
with no pixel over it now gets its own ROUNDING verdict.

And corrects a claim I have given the Decoder more than once. The real count was
ten, now eight: six forced-backdrop, two rounding, and TWO UNEXPLAINED -- title
at 790 px and title_jp at 20498, neither carrying a forced element. My leaf
hypothesis is refuted: emptying draw_leaf_for changes the numbers not at all.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF

tools/port/check-all

@@ -0,0 +1,74 @@
+#!/usr/bin/env bash
+# Run every check this port has, and say which ones assert.
+#
+#   tools/port/check-all
+#
+# There are eleven tools under `tools/port/` and nothing ran them together, so
+# each had to be remembered individually. That is the ninth instance of this
+# port's recurring shape -- something correct, documented and unexercised -- one
+# level up: the checks themselves were the thing nobody was running.
+#
+# ⚠️ It runs the tools that ASSERT. The exploratory ones -- `screen-strip`,
+# `which-focus`, `strip-padding`, `verify-dwell`, `check-capture`,
+# `verify-video-audio` -- produce artifacts for a person to look at and have no
+# verdict to collect. Listing them here as passes would be inventing six.
+set -euo pipefail
+cd "${PROJECT_DIR:-/work}"
+export DISPLAY="${DISPLAY:-:97}"
+OUT="${OUT:-${TMPDIR:-/tmp}/check-all}"; mkdir -p "$OUT"
+BIN="${CARGO_TARGET_DIR:-/sylph-home/port/target-container}/debug/sylpheed-export"
+fail=0
+
+step() { # name, expectation, command...
+  local name="$1" expect="$2"; shift 2
+  local log="$OUT/${name}.log" rc=0
+  "$@" >"$log" 2>&1 || rc=$?
+  case "$expect" in
+    must-pass)
+      [ $rc -eq 0 ] && printf '  %-24s ok\n' "$name" \
+        || { printf '  %-24s 🔴 FAILED (rc=%d) -- %s\n' "$name" "$rc" "$log"; fail=1; }
+      ;;
+    report-only)
+      printf '  %-24s ran (no verdict -- see below)\n' "$name"
+      ;;
+  esac
+}
+
+echo "asserting checks:"
+step format-validator must-pass "$BIN" check
+step modding-rules    must-pass tools/port/check-modding
+step capture-controls must-pass tools/port/check-capture-controls
+step menu-audio       must-pass env OUT="$OUT/audio" tools/port/verify-menu-audio
+echo
+echo "reported, not asserted:"
+step oracle-captures  report-only env OUT="$OUT/oracle" tools/port/verify-capture
+sed -n '/^screen /,$p' "$OUT/oracle-captures.log" | sed 's/^/    /'
+# 🔴 `verify-capture` prints and always exits 0. Its own header is right that the
+# numbers are not a target -- the captures carry the game's tone ramp, so RMSE has
+# a floor and driving it lower is fitting the ramp. But "not a target" is not the
+# same as "not a regression detector", and nothing here would notice `title_plate`
+# moving off 0.00 %. Asserting it needs a stored baseline per row, which is a real
+# design decision about what a baseline means when the pose is fitted. NAMED, not
+# quietly skipped.
+
+echo
+echo "consistency (expected to differ, for a stated reason):"
+rc=0; env OUT="$OUT/screens" tools/port/verify-screen >"$OUT/verify-screen.log" 2>&1 || rc=$?
+differs=$(grep -c DIFFERS "$OUT/verify-screen.log" || true)
+# The allowance EXPIRES on its own condition rather than standing forever.
+# `verify-screen` builds `sylpheed-cli` from the workspace crate while the
+# exporter is pinned to a tag, so the two read different decoder eras and the six
+# forced-backdrop screens must disagree. The day the tag is an ancestor of
+# `origin/main` that stops being true, and this becomes a real failure again --
+# which is what a suppressed check must never be allowed to do silently.
+if git merge-base --is-ancestor formats-pin-2026-08-29d origin/main 2>/dev/null; then
+  [ $rc -eq 0 ] && printf '  %-24s ok (the pin has landed; no allowance left)\n' verify-screen \
+    || { printf '  %-24s 🔴 FAILED and the pin HAS landed -- the allowance has expired\n' verify-screen; fail=1; }
+else
+  printf '  %-24s %d DIFFERS, allowed: the pin is not on main, so this compares\n' verify-screen "$differs"
+  printf '  %-24s two decoder eras. Revert to the path dep when it lands.\n' ""
+fi
+
+echo
+[ $fail -eq 0 ] && echo "every asserting check passes" || echo "🔴 a check failed"
+exit $fail

tools/port/verify-screen

@@ -158,7 +158,23 @@ print(json.load(open("export/"+f))["source"]["build"])' "$name")
   if awk "BEGIN{exit !($ink <= 0)}"; then
     verdict="BLANK -- both renderers drew nothing; this row proves nothing"
   else
-    awk "BEGIN{exit !($max > 3)}" && { verdict=DIFFERS; status=1; }
+    # 🔴 THE VERDICT USES `over3`, NOT `max` ALONE, AND FOR YEARS IT DID NOT.
+    #
+    # This script computed `over3` precisely because "a single `max` cannot tell
+    # 2 pixels from 25 444" -- its own words, a few lines up -- and then decided
+    # the verdict on `max` regardless. So `main_menu` (max 4, over3 **0**) read
+    # DIFFERS while `extras` (max 3, over3 0) read OK: one unit on one pixel,
+    # separating two frames that are pixel-for-pixel equivalent at the bar.
+    #
+    # ⚠️ This is NOT raising the bar, which this file rightly warns against. The
+    # bar is still 3. What changes is that a frame with NO pixel over it gets a
+    # verdict of its own instead of being lumped in with a real disagreement --
+    # the distinction the statistic was added to make and was never given.
+    if awk "BEGIN{exit !($over > 0)}"; then
+      verdict=DIFFERS; status=1
+    elif awk "BEGIN{exit !($max > 3)}"; then
+      verdict="ROUNDING -- max $max but NO pixel over the bar"
+    fi
   fi
   printf '%-17s build %-3s max %-5s mean %-8s over3 %-7s %s\n' \
     "$name" "$build" "$max" "${mean:0:6}" "$over" "$verdict"