Generate sub-bullets for RubyGems and bundler

RubyGems and bundler were skipped outright in collect_gem_updates, so
NEWS.md never picked up the rubygems/rubygems releases shipped between
the X.Y.0 baseline and the in-development X.(Y+1).0.dev. Wire them
through resolve_repo (RubyGems → rubygems/rubygems, bundler same repo
with a "bundler-" tag prefix) and teach fetch_release_range to filter
and look up tags by that prefix. Display tags strip the prefix so the
rendered diff reads "4.0.3 to v4.0.4, ..." for both gems while the
footnote URLs still point at the actual tag names. When the "to"
version ends in .dev/.beta/.rc/etc., the lookup falls back to the
highest released tag so unreleased dev versions still produce a range.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hsbt

tool/update-NEWS-github-release.rb

@@ -206,12 +206,16 @@ def resolve_repo(name)
     { repo: name, org: "minitest" }
   when "test-unit"
     { repo: name, org: "test-unit" }
+  when "RubyGems"
+    { repo: "rubygems", org: "rubygems" }
+  when "bundler"
+    { repo: "rubygems", org: "rubygems", tag_prefix: "bundler-" }
   else
     { repo: name, org: "ruby" }
   end
 end
 
-def fetch_release_range(name, from_version, to_version, org, repo)
+def fetch_release_range(name, from_version, to_version, org, repo, tag_prefix: "")
   releases = []
   begin
     Octokit.releases("#{org}/#{repo}").each do |release|
@@ -222,12 +226,18 @@ def fetch_release_range(name, from_version, to_version, org, repo)
     return nil
   end
 
-  # Keep only version-like tags and sort ascending by semantic version
-  releases = releases.select { |t| t =~ /^v\d/ || t =~ /^\d/ }
-  releases = releases.sort_by { |t| Gem::Version.new(t.sub(/^v/, "").tr("_", ".")) }
+  # Keep only this gem's version-like tags and sort ascending by semantic version
+  prefix = Regexp.escape(tag_prefix)
+  releases = releases.select { |t| t =~ /\A#{prefix}v?\d/ }
+  releases = releases.sort_by { |t| Gem::Version.new(t.sub(/\A#{prefix}/, "").sub(/^v/, "").tr("_", ".")) }
+
+  start_index = releases.index("#{tag_prefix}v#{from_version}") || releases.index("#{tag_prefix}#{from_version}")
+  end_index = releases.index("#{tag_prefix}v#{to_version}") || releases.index("#{tag_prefix}#{to_version}")
+
+  # If the "to" version is unreleased (e.g. 4.1.0.dev), include every released
+  # tag after the baseline up to the latest one available.
+  end_index ||= releases.length - 1 if to_version =~ /(?:\.|-)(?:dev|beta|alpha|rc|pre)/i
 
-  start_index = releases.index("v#{from_version}") || releases.index(from_version)
-  end_index = releases.index("v#{to_version}") || releases.index(to_version)
   return nil unless start_index && end_index
 
   range = releases[start_index + 1..end_index]
@@ -242,18 +252,19 @@ def collect_gem_updates(versions_from, versions_to)
   versions_to.each do |name, version|
     # Skip items which do not exist in the FROM map to reduce API calls
     next unless versions_from.key?(name)
-    next if name == "RubyGems" || name == "bundler"
 
     info = resolve_repo(name)
     org = info[:org]
     repo = info[:repo]
+    tag_prefix = info[:tag_prefix] || ""
 
-    release_range = fetch_release_range(name, versions_from[name], version, org, repo)
+    release_range = fetch_release_range(name, versions_from[name], version, org, repo, tag_prefix: tag_prefix)
     next unless release_range
 
     footnote_links = release_range.map do |rel|
+      tag = rel.sub(/\A#{Regexp.escape(tag_prefix)}/, "")
       {
-        ref: "#{name}-#{rel}",
+        ref: "#{name}-#{tag}",
         url: "https://github.com/#{org}/#{repo}/releases/tag/#{rel}",
       }
     end
@@ -264,15 +275,18 @@ def collect_gem_updates(versions_from, versions_to)
       from_version: versions_from[name],
       release_range: release_range,
       footnote_links: footnote_links,
+      tag_prefix: tag_prefix,
     }
   end
 
   results
 end
 
 def format_release_diff(result)
+  prefix = Regexp.escape(result[:tag_prefix] || "")
   links = result[:release_range].map do |rel|
-    "[#{rel}][#{result[:name]}-#{rel}]"
+    tag = rel.sub(/\A#{prefix}/, "")
+    "[#{tag}][#{result[:name]}-#{tag}]"
   end
   "  * #{result[:from_version]} to #{links.join(', ')}"
 end