Simplify Gardener Slack notifications to linked titles

.github/workflows/gardener-notify-slack.yml

@@ -1,6 +1,6 @@
 name: Gardener - Notify Slack
 # Runs after `Gardener - Notify Event` completes and does the real work:
-# applies the devtools-gardener label and posts a summary to Slack.
+# applies the devtools-gardener label and posts a repo-prefixed linked title to Slack.
 #
 # The workflow_run trigger runs this job in the default-branch context with
 # full GITHUB_TOKEN permissions and Actions secret access — this is what
@@ -59,57 +59,16 @@ jobs:
           SLACK_BOT_TOKEN: ${{ secrets.SLACK_GARDENER_BOT_TOKEN }}
           SLACK_CHANNEL_ID: ${{ vars.GARDENER_SLACK_CHANNEL_ID }}
         run: |
-          KIND=$(jq -r 'if has("pull_request") then "PR" else "Issue" end' event.json)
-          # Pull the body out, truncate, then convert GitHub Markdown to
-          # Slack mrkdwn. Links and fenced code blocks are stashed before
-          # the HTML-escape pass so their contents survive verbatim (a `&`
-          # inside a URL must stay raw, and code content shouldn't be
-          # mangled). Blockquote `> ` markers are also stashed so the
-          # `>` → `>` escape doesn't break them. Everything else is
-          # HTML-escaped so user-supplied `<`, `>`, `&` can't collide
-          # with Slack link syntax or injected mentions like <!channel>.
-          BODY=$(jq -r '(.issue // .pull_request).body // ""' event.json)
-          if [ ${#BODY} -gt 1000 ]; then
-            BODY="${BODY:0:1000}…"
-          fi
-          BODY=$(printf '%s' "$BODY" | perl -0777 -pe '
-            my @u;
-            s{\[([^\]]+)\]\(([^)]+)\)}{push @u, $2; "\x01$#u\x02$1\x03"}ge;
-            my @c;
-            s{^```[^\n]*\n(.*?)\n```$}{push @c, $1; "\x04$#c\x05"}gems;
-            s/^> /\x06/gm;
-            s/^#{1,6}\s+(.+)$/*$1*/gm;
-            s/\*\*(.+?)\*\*/*$1*/g;
-            s/^(\s*)- \[x\]\s+/$1✓ /gm;
-            s/^(\s*)[-*]\s+/$1• /gm;
-            s/&/&amp;/g;
-            s/</&lt;/g;
-            s/>/&gt;/g;
-            s/\x06/> /g;
-            s{\x01(\d+)\x02(.*?)\x03}{"<$u[$1]|$2>"}ge;
-            s{\x04(\d+)\x05}{"```\n$c[$1]\n```"}ge;
-          ')
           jq \
             --arg channel "$SLACK_CHANNEL_ID" \
-            --arg kind "$KIND" \
-            --arg body "$BODY" \
             '
               def escape: gsub("&";"&amp;") | gsub("<";"&lt;") | gsub(">";"&gt;");
 
               (.issue // .pull_request) as $i
-              | ([$i.labels[]?.name | select(. != "devtools-gardener")]
-                  | map("`\(.)`") | join(" ")) as $labels
-              | (if $kind == "PR"
-                  then " · \($i.changed_files) files, +\($i.additions)/-\($i.deletions)"
-                       + (if $i.draft then " · draft" else "" end)
-                  else "" end) as $meta
-              | [ "*<\($i.html_url)|\($kind) #\($i.number)>* — \(($i.title | escape))",
-                  "_opened by \($i.user.login)\($meta)_" ]
-                + (if $body != "" then [$body] else [] end)
-                + (if $labels != "" then [$labels] else [] end)
-              | join("\n") as $msg
-              | { channel: $channel, text: "\($kind) #\($i.number): \($i.title)",
-                  blocks: [{ type: "section", text: { type: "mrkdwn", text: $msg } }] }
+              | { channel: $channel,
+                  text: "\(.repository.name) · <\($i.html_url)|\($i.title | escape)>",
+                  unfurl_links: false,
+                  unfurl_media: false }
             ' event.json | curl -sf -X POST \
               -H "Authorization: Bearer $SLACK_BOT_TOKEN" \
               -H 'Content-type: application/json; charset=utf-8' \