[prototype] Product sync feed status UI

[haszari]

Related to #2007

Changes proposed in this Pull Request:

This PR is a prototype UI for showing the status of the product feed (data source) and potentially guiding merchant to set it up. It's not intended to ship as is – is a starting point for deciding what minimal UI we need in 2.7.

• A new section is added to the Marketing > Facebook > Product sync tab. Feed UI / info should be on this tab as it's part of syncing products (should not be a separate tab).
• In this section, there are three items, for 3 aspects of the feed:
  • If it is configured and set up (correctly).
  • The status of generating the feed file.
  • The status of the sync, i.e. if it's been pulled ("uploaded") to Facebook, and any errors.

I've prototyped a mini "component" (in PHP - see render_status_item()) to generically prototype all these and give us some flexibility. Note this is not completely implemented (e.g. colours, no copy to clipboard), just a sketch to help prototype.

The component has the following params, most are optional:

• label The main heading label on the left.
• text The primary text status / info label (on the right).
• status An optional status (success error warning) to add colour and an icon.
• help_tip Tooltip for the help icon button.
• Inline link - e.g. for linking to help or to Facebook business settings (or elsewhere in Woo admin).
  • link_label Link label text.
  • link_url Link destination URL.
  • link_is_external Specify true to show the "external" icon.
• info_text Additional status/detailed info, rendered smaller. E.g. last sync results.
• Clipboard link - e.g. for copying the feed URL so you can configure a data source in Facebook (minimal setup UI).
  • clipboard_label Label / prompt.
  • clipboard_content Text to copy to clipboard.

Feed status prototypes

How to test the changes in this Pull Request:

tbc

Changelog entry

tbc

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