post: QR pre-download decode gate (EN+ZH) + Argon batch-10 review

- 69-module symbol at 20 mm = 0.29 mm/module, refused below a 0.40 mm floor
- 30% centre image on a 29-module symbol knocks out 19% of area, capped at 15%
- maroon #800000 passes WCAG at 10.9:1 but is 1.9:1 on the red channel, so warn only
- 300 dpi export quoted at 50.1 x 56.9 mm with the caption band and pHYs block
- gate reads every code back with jsQR at two densities before the download unlocks
- batch-10 external review: 94/96/88/100, 10 items applied, 2 rejected with reasons

scripts/og-gen/art-meta.json

@@ -369,5 +369,10 @@
   "evidence": "6 seats - 9 s - 403 to 502 mapping",
   "ogTitle_en": "The Gateway That Tripped Trust & Safety",
   "ogTitle_zh": "网关撞上风控"
+ },
+ "qr-gate-that-decodes-before-the-download": {
+  "evidence": "69 modules @ 20 mm · 0.29 mm/module · floor 0.40 mm",
+  "ogTitle_en": "Decode Before Download",
+  "ogTitle_zh": "先解码，再给下载"
  }
 }

scripts/og-gen/banner-plan.json

@@ -1108,6 +1108,30 @@
     768
    ]
   },
+  "qr-gate-that-decodes-before-the-download": {
+   "sw": 2223,
+   "sh": 1256,
+   "left": 795,
+   "top": 143,
+   "fill": [
+    11,
+    18,
+    24
+   ],
+   "zoom": 1.635,
+   "silhouette": 0.47,
+   "cut": 0.0,
+   "band": [
+    780,
+    120,
+    1240,
+    605
+   ],
+   "source_size": [
+    1360,
+    768
+   ]
+  },
   "read-amplification-504-gateway-timeout-swr-cache": {
    "sw": 1944,
    "sh": 1098,
@@ -1948,6 +1972,30 @@
     768
    ]
   },
+  "when-a-self-hosted-model-router-tripped-trust-and-safety": {
+   "sw": 1930,
+   "sh": 1090,
+   "left": 604,
+   "top": 102,
+   "fill": [
+    14,
+    18,
+    30
+   ],
+   "zoom": 1.419,
+   "silhouette": 0.47,
+   "cut": 0.0,
+   "band": [
+    764,
+    123,
+    1294,
+    655
+   ],
+   "source_size": [
+    1360,
+    768
+   ]
+  },
   "when-lowering-crf-does-nothing-maxrate-deadlock": {
    "sw": 1930,
    "sh": 1090,
@@ -2403,30 +2451,6 @@
     1360,
     768
    ]
-  },
-  "when-a-self-hosted-model-router-tripped-trust-and-safety": {
-   "sw": 1930,
-   "sh": 1090,
-   "left": 604,
-   "top": 102,
-   "fill": [
-    14,
-    18,
-    30
-   ],
-   "zoom": 1.419,
-   "silhouette": 0.47,
-   "cut": 0.0,
-   "band": [
-    764,
-    123,
-    1294,
-    655
-   ],
-   "source_size": [
-    1360,
-    768
-   ]
   }
  }
 }