Registry changelogs as plain text

The registry shows a version's changelog as one paragraph, without Markdown
or line breaks: a shared script turns the CHANGELOG.md section into
'Added: ...; ... Fixed: ...' for both the publish and the update workflows.

.github/scripts/registry_changelog.py

@@ -0,0 +1,74 @@
+"""Print a version's CHANGELOG.md section as plain text for the Comfy Registry.
+
+The registry shows a version's changelog as one paragraph: line breaks and
+Markdown are not rendered. So headings become "Added:", "Fixed:"..., list
+items are joined with "; ", and Markdown markup is dropped.
+
+    python .github/scripts/registry_changelog.py 1.2.2
+    python .github/scripts/registry_changelog.py --all   # JSON {version: text}
+"""
+
+import json
+import re
+import sys
+
+
+def sections(path="CHANGELOG.md"):
+    out, current = {}, None
+    for line in open(path, encoding="utf-8").read().splitlines():
+        m = re.match(r"^## (\d+\.\d+\.\d+)\b", line)
+        if m:
+            current = m.group(1)
+            out[current] = []
+        elif line.startswith("## "):
+            current = None
+        elif current:
+            out[current].append(line)
+    return out
+
+
+def plain(text):
+    text = re.sub(r"\[([^\]]+)\]\([^)]+\)", r"\1", text)  # links: keep the text
+    text = re.sub(r"\*\*([^*]+)\*\*", r"\1", text)
+    text = re.sub(r"(?<!\w)\*([^*]+)\*(?!\w)", r"\1", text)
+    return text.replace("`", "").strip()
+
+
+def registry_text(lines):
+    parts, heading, items, intro = [], None, [], []
+
+    def flush():
+        if items:
+            body = "; ".join(i.rstrip(".") for i in items) + "."
+            parts.append(f"{heading}: {body}" if heading else body)
+
+    for raw in lines:
+        line = raw.strip()
+        if not line:
+            continue
+        if line.startswith("### "):
+            flush()
+            heading, items = plain(line[4:]), []
+        elif line.startswith("- "):
+            items.append(plain(line[2:]))
+        elif items:
+            items[-1] += " " + plain(line)  # a wrapped list item
+        else:
+            intro.append(plain(line))
+    flush()
+    return " ".join(intro + parts).strip()
+
+
+def main():
+    sys.stdout.reconfigure(encoding="utf-8")
+    all_sections = sections()
+    if sys.argv[1:] == ["--all"]:
+        print(json.dumps({v: registry_text(lines) for v, lines in all_sections.items()}, ensure_ascii=False))
+    elif len(sys.argv) == 2:
+        print(registry_text(all_sections.get(sys.argv[1], [])))
+    else:
+        sys.exit(__doc__)
+
+
+if __name__ == "__main__":
+    main()