Upgrade to Ruby 3.4, Bundler 4, fix frozen string literal warning, update workflows

- Set .ruby-version to 3.4.4 for local development
- Update Bundler from 2.4.13 to 4.0.13 and update gems
- Replace mutable '' with String.new in run.rb to fix Ruby 3.4 frozen string warning
- Update test.yml: use ubuntu-24.04, actions/checkout@v4, Ruby 3.2/3.3/3.4 matrix
- Add release.yml for trusted publishing to RubyGems.org

Author: jeremiahlukus

.github/workflows/release.yml

@@ -0,0 +1,26 @@
+name: Release Gem
+on:
+  workflow_dispatch:
+    branches:
+      - master
+
+jobs:
+  push:
+    name: Push gem to RubyGems.org
+    runs-on: ubuntu-latest
+
+    permissions:
+      id-token: write # IMPORTANT: this permission is mandatory for trusted publishing
+      contents: write # IMPORTANT: this permission is required for `rake release` to push the release tag
+
+    steps:
+      # Set up
+      - uses: actions/checkout@v4
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          bundler-cache: true
+          ruby-version: ruby
+
+      # Release
+      - uses: rubygems/release-gem@v1

.github/workflows/test.yml

@@ -2,17 +2,16 @@ name: CI/CD
 on: [push]
 jobs:
   build:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     name: Ruby ${{ matrix.ruby }}
     strategy:
       matrix:
         ruby:
-          - "2.7.4"
-          - "3.0.2"
-          - "3.1.0"
-          - "3.2.1"
+          - "3.2"
+          - "3.3"
+          - "3.4"
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Ruby
         uses: ruby/setup-ruby@v1
         with:

.ruby-version

@@ -0,0 +1 @@
+3.4.4

Gemfile.lock

@@ -6,14 +6,19 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    minitest (5.18.0)
-    mocha (2.0.4)
+    drb (2.2.3)
+    minitest (6.0.6)
+      drb (~> 2.0)
+      prism (~> 1.5)
+    mocha (3.1.0)
       ruby2_keywords (>= 0.0.5)
-    rake (13.0.6)
+    prism (1.9.0)
+    rake (13.4.2)
     ruby2_keywords (0.0.5)
 
 PLATFORMS
   arm64-darwin-22
+  arm64-darwin-25
   x86_64-linux
 
 DEPENDENCIES
@@ -23,4 +28,4 @@ DEPENDENCIES
   rake
 
 BUNDLED WITH
-   2.4.13
+  4.0.13

lib/lambda-console-ruby/run.rb

@@ -22,7 +22,7 @@ def handle(event)
 
     def initialize(event)
       @event = event
-      @body = ''
+      @body = String.new
     end
 
     def run