Refactor deep link connection handling and connectSite mutation

[epeicher]

Related issues

• Solves STU-1086
• Follow up of this comment - Implement RTK Query approach for fetching wpcom sites #2132 (comment)

Proposed Changes

• Simplified the useListenDeepLinkConnection hook by removing unnecessary queries and directly using the connectSite function with updated parameters.
• Updated the handleConnect function in ContentTabSync to accept remoteSiteId instead of a full site object, streamlining the connection process.
• Enhanced the connectSite mutation in the Redux slice to handle remote site connections more effectively, including error handling for site not found scenarios.

Testing Instructions

Connect a site via the Sync tab

• Select a local site, go to the Sync tab, connect a WordPress.com site, and verify it connects successfully.

Deep link connection

• Trigger a deep link connection (e.g., via WordPress.com "Connect to Studio" flow). Verify the correct local site is selected, the Sync tab opens, and the site connects. One example could be: wp-studio://sync-connect-site?studioSiteId=<local_studio_id>&remoteSiteId=<remote_blog_id>

Deep link with auto-open push

• Create a Studio site or open one that is not connected to WP.com, select Publish site, and follow the process to create the site
• Click on Open in Studio
• Verify that the Sync modal open as expected.

Add a new connected site

• Click Add Site
• Choose Connect to a WordPress.com site and select a remote site
• Fill in the site name and create the site
• Verify the new local site is created and it starts pulling from the remote site (you should see the Sync tab activate with a pull in progress)

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[wpmobilebot]

📊 Performance Test Results

Comparing df3ea3a vs trunk

site-editor

Metric	trunk	df3ea3a	Diff	Change
load	1486.00 ms	1479.00 ms	-7.00 ms	⚪ 0.0%

site-startup

Metric	trunk	df3ea3a	Diff	Change
siteCreation	7092.00 ms	7085.00 ms	-7.00 ms	⚪ 0.0%
siteStartup	4948.00 ms	4909.00 ms	-39.00 ms	⚪ 0.0%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change (<50ms diff)

[katinthehatsite]

One this is that we might want to double-check this with https://github.com/Automattic/studio/pull/2375/commits as they are likely going to overlap 😅

[katinthehatsite]

Also, perhaps this PR already solves the issue from the other PR - I will give it a test now 👀

[katinthehatsite]

I did not finish testing everything yet but I noticed that there is a small delay for me when I click on Connect site or Connect another site:

Screen.Recording.2026-02-26.at.11.18.18.AM.mov

Initially, I thought that it was not connecting so I clicked multiple times before seeing it connect. In the second try, I click and waited and then it connected. I think if we have the small delay, we should probably set the Connect button to loading state to indicate to the user that the connection is happening.

[katinthehatsite]

There are two more calls for handleConnect in this file in onPull and onPush - do we also need to adjust passing an id there now that it expects a number?

[epeicher]

Well spotted! That code might be called when using deeplinks and it needed to be updated accordingly! Done as part of f78b4fd

[epeicher]

One this is that we might want to double-check this with https://github.com/Automattic/studio/pull/2375/commits as they are likely going to overlap 😅

Ok, this can wait for that PR to be merged, this PR is not urgent as it is a refactor

[epeicher]

I think if we have the small delay, we should probably set the Connect button to loading state to indicate to the user that the connection is happening.

Absolutely, that will improve the UX. I will compare also with trunk and check if there are differences, but anyway, adding a loading state will prevent confusion