fix: Livechat popout not syncing department and custom fields

[aleksandernsilva]

Proposed changes (including videos or screenshots)

Google’s privacy changes (specifically storage partitioning) have affected how localStorage works across iframes and child windows. As a result, Livechat's popout mode lost access to shared state and became less reactive.

This PR is the first step toward restoring reactivity in popout mode. It initializes the popout window with the token, iframe data, and custom fields queue.

Future work will expand this logic to cover the rest of the Livechat internal state to fully restore reactivity to the popout mode.

Issue(s)

CTZ-156
CTZ-204

Steps to test or reproduce

⚠️ To be able to properly test this you must embed Livechat in a different origin.

• Embed Livechat in a different origin
• set custom field, department and/or theme data

window.RocketChat(function() {
   this.setTheme({ color: 'rebeccapurple' });
   this.setDepartment('departmentid');
   this.setCustomField('customfield', 'value')
})

• Click "Expand chat" in the Livechat widget header
• New window should open (popout) with the information pre-loaded

Further comments

[dionisio-bot]

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[changeset-bot]

⚠️ No Changeset found

Latest commit: 467297e

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[github-actions]

PR Preview Action v1.6.1
🚀 View preview at https://RocketChat.github.io/Rocket.Chat/pr-preview/pr-36125/
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 64.46%. Comparing base (9fd2be4) to head (467297e).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #36125      +/-   ##
===========================================
+ Coverage    63.96%   64.46%   +0.50%     
===========================================
  Files         3058     3138      +80     
  Lines       103632   104921    +1289     
  Branches     19471    19789     +318     
===========================================
+ Hits         66284    67638    +1354     
+ Misses       34728    34602     -126     
- Partials      2620     2681      +61     

Flag	Coverage Δ
e2e	57.66% <ø> (+1.65%)	⬆️
unit	69.07% <ø> (+0.04%)	⬆️

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[scuciatto]

/patch

[dionisio-bot]

Pull request #36299 added to Project: "Patch 7.7.2"