ci(regen): stop the weekly no-op update PR

The Telegram page ends with a "page generated in NN.NNms" comment that
changes on every fetch. Change detection saw it, so the run dispatched after
the codegen fix opened and merged a PR whose only content was that comment.
With the merge step in place, that becomes a pointless release every week.

Strip the comment on capture, and gate change detection on the generated
surface instead of testdata/html/, because the snapshot file name and the
latest.html symlink change every run by design. A fresh fetch now matches the
committed snapshot byte for byte while the API is unchanged.

.github/workflows/regen.yml

@@ -29,7 +29,12 @@ jobs:
           DATE=$(date +%Y-%m-%d)
           DEST="testdata/html/snapshot_${DATE}.html"
           curl -fsSL --user-agent "go-telegram codegen scraper" \
-            https://core.telegram.org/bots/api > "$DEST"
+            https://core.telegram.org/bots/api -o "$DEST.tmp"
+          # The page ends with a "<!-- page generated in NN.NNms -->" comment
+          # that changes on every fetch. Drop it, so an unchanged API produces
+          # a byte-identical snapshot instead of a no-op update PR.
+          sed '/<!-- page generated in .*ms -->/d' "$DEST.tmp" > "$DEST"
+          rm "$DEST.tmp"
           ln -sf "snapshot_${DATE}.html" testdata/html/latest.html
           echo "date=$DATE" >> $GITHUB_OUTPUT
           echo "dest=$DEST" >> $GITHUB_OUTPUT
@@ -76,7 +81,10 @@ jobs:
         id: diff
         run: |
           git status --porcelain
-          if git diff --quiet internal/spec/api.json api/ testdata/html/; then
+          # Gate on the generated surface only. A fresh snapshot file and the
+          # latest.html symlink flip every run, so including testdata/html/
+          # here would open a PR on a week when Telegram changed nothing.
+          if git diff --quiet internal/spec/api.json api/ docs/reference/; then
             echo "no_changes=true" >> $GITHUB_OUTPUT
           fi
 

testdata/html/snapshot_2026-07-21.html

@@ -23112,4 +23112,3 @@ removePreloadInit();
 </script>
   </body>
 </html>
-<!-- page generated in 133.23ms -->