[Onboarding] Walkthrough: Deploy Prompt

[mmabrouk]

Parent: #3051

Summary

Implement a guided tour that teaches users how to deploy a prompt version and access it via API.

Tour ID: deploy-prompt

Completion event: variant_deployed

Behind env var: NEXT_PUBLIC_ENABLE_WALKTHROUGHS=true

Steps

#	Icon	Title	Content	Selector
1	🚀	Deploy Your Prompt	Once you have a prompt version you like, you can deploy it to an environment. Let me show you how.	(centered)
2	📋	Open the Registry	The registry shows all your committed prompt versions. Click here to open it.	[data-tour="registry-nav"]
3	📄	Select a Version	Click on a version to see its details.	[data-tour="version-row"]
4	🌐	Deploy to an Environment	Click Deploy to make this version available via API. You can deploy to staging or production.	[data-tour="deploy-button"]
5	🔗	View the API Code	Click here to see the code snippet for calling your deployed prompt. Copy this into your application.	[data-tour="api-code-button"]

Implementation Tasks

• Add data-tour attributes to registry/deployment UI elements
• Create tour definition in components/Onboarding/tours/
• Register tour with tourRegistry
• Step 5 should open the API code drawer (use onEnter hook)
• Fire variant_deployed event on completion

Acceptance Criteria

• Tour only runs when NEXT_PUBLIC_ENABLE_WALKTHROUGHS=true
• All 5 steps render with correct copy
• Selectors target correct elements
• Step 5 opens the API code drawer
• Completion event fires when tour finishes

[linear]

AGE-3596