feat: add release:bump task for automated version management

Adds rake release:bump[level] task that uses gem-release to bump version, commit, tag, and push automatically. Splits version bumping from changelog generation for better workflow separation.

Author: fidalgo

Rakefile

@@ -16,6 +16,27 @@ end
 task default: %i[test standard]
 
 namespace :release do
+  desc "Bump version (major|minor|patch|pre) and commit"
+  task :bump, [:level] do |_t, args|
+    level = args[:level] || "patch"
+    valid_levels = %w[major minor patch pre]
+
+    unless valid_levels.include?(level)
+      abort "Invalid level: #{level}. Use: #{valid_levels.join(", ")}"
+    end
+
+    branch = `git rev-parse --abbrev-ref HEAD`.strip
+    unless ["main", "master"].include?(branch)
+      abort "Version bump must run on main or master. Current: #{branch}."
+    end
+
+    unless system("git diff --quiet") && system("git diff --cached --quiet")
+      abort "Version bump requires a clean working tree."
+    end
+
+    sh "bundle exec gem bump --version #{level} --commit --tag --push"
+  end
+
   desc "Update changelog, commit, and tag"
   task :prep do
     version = GitMarkdown::VERSION