R7.7: one source archive pair per release

Windows checks out symlinks as files, so only Linux (CI) and macOS
(release.sh) write source archives. ci.sh skips names already on
the release; the first platform's copy stays.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

scripts/ci.sh

@@ -66,8 +66,10 @@ case $os in
     ;;
 esac
 
-# macOS's release.sh writes its own source archives.
-[ "$os" = macos ] || packaging/source.sh "$dist"
+# Windows checkouts flatten symlinks; Linux and macOS write source.
+if [ "$os" = linux ]; then
+  packaging/source.sh "$dist"
+fi
 
 # The tag's release, made by whichever platform comes first.
 api=https://git.zacharyzhang.com/api/v1/repos/ZacharyZhang-NY/ElyOffice
@@ -79,9 +81,29 @@ if ! id=$(release_id 2>/dev/null); then
   curl -fsS -H "$auth" -H "Content-Type: application/json" -d "$body" "$api/releases" >/dev/null || true
   id=$(release_id)
 fi
+names=()
 for file in "$dist"/*; do
   [ -f "$file" ] || continue
   name=$(basename "$file")
+  # Linux alone publishes the source pair.
+  if [ "$os" != linux ] && [[ $name == *-source.tar.gz ]]; then
+    echo "ci.sh: $name is Linux's to upload"
+    continue
+  fi
+  names+=("$name")
+done
+# Rebuilt bytes differ; never mix them with earlier uploads.
+have=$(curl -fsS -H "$auth" "$api/releases/$id/assets" | python3 -c 'import json, sys; print("\n".join(a["name"] for a in json.load(sys.stdin)))')
+taken=()
+for name in "${names[@]}"; do
+  if grep -qxF "$name" <<<"$have"; then taken+=("$name"); fi
+done
+if [ ${#taken[@]} -gt 0 ]; then
+  echo "ci.sh: already on $tag; delete them, then rerun: ${taken[*]}" >&2
+  exit 1
+fi
+for name in "${names[@]}"; do
+  file=$dist/$name
   echo "ci.sh: uploading $name"
   curl -fsS -H "$auth" -F "attachment=@$file" "$api/releases/$id/assets?name=$name" >/dev/null
 done