feat(ci): render the release notes as Markdown with headings and lists

The release page got the newest <release> block as the plain text of
its paragraphs, which fit two paragraphs of prose and nothing more.
From 3.0.0 the notes group the changes under New, Fixes and Breaking,
each in descending order of importance, and AppStream's description
markup has lists but no headings to carry that.

The metainfo stays the one source of the notes, since the Flatpak
installs it and the tag check reads it. A category is written there as
a paragraph that introduces a list, <p>New</p><ul>...</ul>, which is
how AppStream notes lead into a list anyway, and the CI step renders
such a paragraph as a Markdown heading over its items. A paragraph on
its own stays a paragraph, so the older entries render as before. The
step parses the XML with ElementTree instead of two regexes: entities
are decoded, <em> and <code> get their Markdown spelling, and a code
span keeps text like lib/<triple>/eh from being read as an HTML tag by
the forge.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

.forgejo/workflows/ci.yaml

@@ -185,13 +185,38 @@ jobs:
       - name: Release notes
         if: github.ref_type == 'tag'
         run: |
-          # The newest <release> block's description, as plain text.
+          # The newest <release> block's description as Markdown, for the
+          # release page. AppStream has no headings, so a paragraph that
+          # introduces a list is one: <p>New</p><ul>...</ul> comes out as
+          # "## New" over its items, the shape the notes take since 3.0.0.
+          # A paragraph on its own stays a paragraph, as the older entries
+          # are written. <em> and <code> get their Markdown spelling; a code
+          # span also keeps text such as lib/<triple>/eh from being read as
+          # an HTML tag by the forge.
           python3 - > release-notes.md <<'EOF'
-          import re, html
+          import xml.etree.ElementTree as ET
-          text = open("packaging/flatpak/net.catcrafts.CrafterBuild.metainfo.xml").read()
+
-          block = re.search(r"<release [^>]*>(.*?)</release>", text, re.S).group(1)
+          desc = ET.parse("packaging/flatpak/net.catcrafts.CrafterBuild.metainfo.xml").getroot().find("releases/release/description")
-          paras = re.findall(r"<p>(.*?)</p>", block, re.S)
+
-          print("\n\n".join(html.unescape(" ".join(p.split())) for p in paras))
+          def text(el):
+              parts = [el.text or ""]
+              for child in el:
+                  inner = text(child)
+                  parts.append({"em": f"*{inner}*", "code": f"`{inner}`"}.get(child.tag, inner))
+                  parts.append(child.tail or "")
+              return " ".join("".join(parts).split())
+
+          blocks = list(desc)
+          out = []
+          for i, el in enumerate(blocks):
+              heads_list = i + 1 < len(blocks) and blocks[i + 1].tag in ("ul", "ol")
+              if el.tag == "p":
+                  out.append(f"## {text(el)}" if heads_list else text(el))
+              elif el.tag == "ul":
+                  out.append("\n".join(f"- {text(li)}" for li in el))
+              elif el.tag == "ol":
+                  out.append("\n".join(f"{n}. {text(li)}" for n, li in enumerate(el, 1)))
+          print("\n\n".join(out))
           print("\nInstall:\n\n    flatpak remote-add --if-not-exists catcrafts https://flatpak.catcrafts.net/catcrafts.flatpakrepo\n    flatpak install catcrafts net.catcrafts.CrafterBuild\n")
           EOF
       - name: Publish release