Show Template: Refactor rendering mode management in editor provider and store to persist it

[yogeshbhutkar]

Fixes: #68250

What?

Implements Data Persistence into Preferences Store for Show Template.

Why?

Brings an enhancement to the previous implementation, where, the value set by the user for Show Template would get overwritten by subsequent refresh made to the page.

How?

The store has been updated to consider using preferences store to persist this data.

Testing Instructions

1. Create a new page from the site editor.
2. Change the value from Show Template toggle.
3. Refresh, and observe that the value now persists.

Screencast

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

If you're merging code through a pull request on GitHub, copy and paste the following into the bottom of the merge commit message.

Co-authored-by: yogeshbhutkar <[email protected]>
Co-authored-by: Mamaduka <[email protected]>
Co-authored-by: annezazu <[email protected]>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

[github-actions]

Warning: Type of PR label mismatch

To merge this PR, it requires exactly 1 label indicating the type of PR. Other labels are optional and not being checked here.

• Type-related labels to choose from: [Type] Automated Testing, [Type] Breaking Change, [Type] Bug, [Type] Build Tooling, [Type] Code Quality, [Type] Copy, [Type] Developer Documentation, [Type] Enhancement, [Type] Experimental, [Type] Feature, [Type] New API, [Type] Task, [Type] Technical Prototype, [Type] Performance, [Type] Project Management, [Type] Regression, [Type] Security, [Type] WP Core Ticket, Backport from WordPress Core, Gutenberg Plugin.
• Labels found: .

Read more about Type labels in Gutenberg. Don't worry if you don't have the required permissions to add labels; the PR reviewer should be able to help with the task.