add Stagehand example in Ruby

ruby/hackernews/Gemfile

@@ -0,0 +1,4 @@
+source "https://rubygems.org"
+
+gem "stagehand", "~> 0.6.2"
+gem "dotenv", "~> 3.0"

ruby/hackernews/main.rb

@@ -0,0 +1,119 @@
+require "bundler/setup"
+require "stagehand"
+require "dotenv/load"
+
+SDK_VERSION = "3.0.6"
+
+# Create client using environment variables
+client = Stagehand::Client.new(
+  browserbase_api_key: ENV["BROWSERBASE_API_KEY"],
+  browserbase_project_id: ENV["BROWSERBASE_PROJECT_ID"],
+  model_api_key: ENV["MODEL_API_KEY"]
+)
+
+# Start a new browser session
+start_response = client.sessions.start(
+  model_name: "openai/gpt-4o-mini",
+  x_language: :typescript,
+  x_sdk_version: SDK_VERSION
+)
+
+session_id = start_response.data.session_id
+puts "Session started: #{session_id}"
+puts "Watch live: https://www.browserbase.com/sessions/#{session_id}"
+
+begin
+  # Navigate to Hacker News
+  client.sessions.navigate(
+    session_id,
+    url: "https://news.ycombinator.com",
+    frame_id: "",
+    x_language: :typescript,
+    x_sdk_version: SDK_VERSION
+  )
+  puts "Navigated to Hacker News"
+
+  # Observe available actions
+  observe_response = client.sessions.observe(
+    session_id,
+    instruction: "find the link to view comments for the top post",
+    x_language: :typescript,
+    x_sdk_version: SDK_VERSION
+  )
+
+  actions = observe_response.data.result
+  puts "Found #{actions.length} possible actions"
+
+  if actions.empty?
+    puts "No actions found"
+    exit
+  end
+
+  # Act on the first action
+  action = actions.first
+  puts "Acting on: #{action.description}"
+
+  act_response = client.sessions.act(
+    session_id,
+    input: action.to_h.merge(method: "click"),
+    x_language: :typescript,
+    x_sdk_version: SDK_VERSION
+  )
+  puts "Act completed: #{act_response.data.result[:message]}"
+
+  # Extract structured data
+  extract_response = client.sessions.extract(
+    session_id,
+    instruction: "extract the title and top comment from this page",
+    schema: {
+      type: "object",
+      properties: {
+        title: {
+          type: "string",
+          description: "The title of the post"
+        },
+        top_comment: {
+          type: "string",
+          description: "The text of the top comment"
+        },
+        author: {
+          type: "string",
+          description: "The username of the top commenter"
+        }
+      },
+      required: ["title"]
+    },
+    x_language: :typescript,
+    x_sdk_version: SDK_VERSION
+  )
+  puts "Extracted data: #{extract_response.data.result}"
+
+  # Run autonomous agent
+  execute_response = client.sessions.execute(
+    session_id,
+    execute_options: {
+      instruction: "Navigate back to the main Hacker News page and find the newest post",
+      max_steps: 5
+    },
+    agent_config: {
+      model: Stagehand::ModelConfig::ModelConfigObject.new(
+        model_name: "openai/gpt-4o-mini",
+        api_key: ENV["MODEL_API_KEY"]
+      ),
+      cua: false
+    },
+    x_language: :typescript,
+    x_sdk_version: SDK_VERSION
+  )
+  puts "Agent result: #{execute_response.data.result[:message]}"
+  puts "Agent success: #{execute_response.data.result[:success]}"
+
+ensure
+  # End the session
+  client.sessions.end_(
+    session_id,
+    x_language: :typescript,
+    x_sdk_version: SDK_VERSION
+  )
+  puts "Session ended"
+end