Add typed JSON output to store open

[gonzaloriestra]

WHY are these changes introduced?

Fixes shop/issues-develop#23690.

Scripts need the storefront URL and the outcome of opening the browser as structured data.

WHAT is this pull request doing?

Adds a typed result and discoverable JSON schema to store open, preserving preview access URLs, browser behavior, and terminal messages. Stacked on #8443, continuing the stack from #8441.

Example output

Illustrative sample data. Text excerpts omit terminal decoration and progress. JSON blocks show the final stdout result; progress and diagnostics go to stderr.

shopify store open --store shop.myshopify.com

Text

Opening the storefront for shop.myshopify.com in your browser.

JSON (--json)

{
  "store": "shop.myshopify.com",
  "url": "https://shop.myshopify.com",
  "opened": true
}

Browser could not open

Text

Browser didn't open automatically. Open the storefront manually:
https://shop.myshopify.com

JSON (--json)

{
  "store": "shop.myshopify.com",
  "url": "https://shop.myshopify.com",
  "opened": false
}

How to manually test your changes?

shopify store open --store shop.myshopify.com
shopify store open --store shop.myshopify.com --json
shopify store open --json-schema

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes
• I've considered analytics changes to measure impact
• Added a changeset (consolidated in Add typed JSON output for store delete #8585).