Fix: Hide "View Post" link for non-viewable post types

[R1shabh-Gupta]

What?

Closes #71343

Hides the "View Post" link in the admin bar when editing synced patterns to prevent 404 errors.

Why?

When editing a synced pattern via "Edit original", the "View Post" link in the admin bar still appears and leads to a 404 error because patterns don't have public URLs. This creates a confusing user experience.

How?

Updated the useUpdatePostLinkListener hook to check if the current post type is viewable using postType?.viewable. For non-viewable post types, the "View Post" link is hidden using display: none.

Testing Instructions

1. Open a new playground
2. Open "Hello World" post in block editor from admin bar or post list in WP-Admin
3. Disable "full screen mode"
4. Insert some block(s) and convert them to a synced pattern
5. Save the post
6. Enter edit mode for that synced pattern via "Edit original" in tools bar
7. Verify that the "View Post" button in the admin bar is now hidden
8. Go back to editing the original post and confirm the "View Post" link is visible again

Screenshots or screencast

Before

Screen.Recording.2025-08-26.at.8.12.45.PM.mov

After

Screen.Recording.2025-08-26.at.8.11.00.PM.mov

[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: R1shabh-Gupta <rishabhwp@git.wordpress.org>
Co-authored-by: t-hamano <wildworks@git.wordpress.org>
Co-authored-by: sabernhardt <sabernhardt@git.wordpress.org>

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

[R1shabh-Gupta]

Hey @t-hamano,
Could you take a look at the PR when you get a chance? The "View Post" option is now hidden for all post types that are not viewable, using the approach you described in the issue comment.

I’d appreciate any feedback or suggestions you might have.

[t-hamano]

Thanks for the PR!

I think we need to restore the link again when we "back" from the synced pattern editing screen.

[t-hamano]

LGTM 👍