feat: report a published export that fell behind

exports/ is committed but CI cannot rebuild it, since the originals it
patches live in the local cache. The native freshness check now runs
the export offline and compares it with the committed files, and
refresh_stale writes the export again after refreshing an original.

scripts/refresh_stale.py

@@ -14,7 +14,8 @@ Mapping (stale -> command):
                             the export patches must be the one just scraped
     native/<name>           python scripts/generate_truth.py --platform <name>, then
                             python scripts/export_native.py --platform <name>
-                            --refresh-cache
+                            --refresh-cache, then the export itself, which
+                            rewrites exports/<name>
     targets/<name>          python -m scripts.scraper.targets.<module>
                             -o platforms/targets/<name>.yml
     data/<key>              python scripts/refresh_data_dirs.py --key <key>
@@ -172,9 +173,13 @@ def plan_jobs(
         if area == "platforms":
             # The truth reads the platform file: regenerated first, or the
             # native refresh refuses it as older than the profiles.
-            then = (tuple(_truth_refresh(subject)), tuple(_native_refresh(subject)))
+            then = (
+                tuple(_truth_refresh(subject)),
+                tuple(_native_refresh(subject)),
+                tuple(_export_refresh(subject)),
+            )
         elif area == "native":
-            then = (tuple(_native_refresh(subject)),)
+            then = (tuple(_native_refresh(subject)), tuple(_export_refresh(subject)))
         jobs.append(
             Job(area=area, subject=subject, command=command, log_path=log, then=then)
         )
@@ -196,6 +201,11 @@ def _native_refresh(platform: str) -> list[str]:
     ]
 
 
+def _export_refresh(platform: str) -> list[str]:
+    """Rewrite the published export from the refreshed original."""
+    return [sys.executable, "scripts/export_native.py", "--platform", platform]
+
+
 def _command_for(
     area: str, subject: str, registry: dict[str, dict]
 ) -> list[str] | None: