MM-26917 update channel header message format

[Akanshagore]

Summary

Updated the channel header system message format to show the changes in a clearer From/To format.

Changes

• Updated the channel header system message translation format in assets/base/i18n/en.json.
• Updated the system message renderer unit test and snapshot for the new From/To format.
• Added separate lines for From and To values to improve readability.

Ticket

MM-26917

Testing

Run:
npx jest app/components/post_list/post/system_message/system_message_helpers.test.js -u

Result:
9 tests passed.

Checklist

• Added or updated unit tests (required for all new features)
• Has UI changes
• Includes text changes and localization file updates
• Have tested against the 5 core themes to ensure consistency between them.
• Have run E2E tests by adding label E2E/Run (or E2E/Run-iOS / E2E/Run-Android for platform-specific runs).

Device Information

This PR was tested on: Not tested

Screenshots

N/A

Release Note

Updated channel header system message format to display changes with From and To fields.

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[coderabbitai]

📝 Walkthrough

Walkthrough

The channel-header system message now displays the previous and new headers on separate labelled lines. The labels use Markdown emphasis.

Changes

Channel Header Formatting

Layer / File(s)	Summary
Update channel-header message text app/components/post_list/post/system_message/system_message.tsx, assets/base/i18n/en.json, app/components/post_list/post/system_message/system_message_helpers.test.js	The message and English translation use separate Markdown-formatted From and To lines. Tests verify the description, labels, and header values.

Estimated code review effort: 1 (Trivial) | ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly identifies the channel header message format update and includes the relevant ticket identifier.
Description check	✅ Passed	The description clearly explains the From/To format change, related file updates, testing, and release note.

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@app/components/post_list/post/system_message/system_message.tsx`:
- Line 94: Update the renderer test covering the channel-header system message
in the system message helpers test to expect the new separate “From” and “To”
lines, and refresh its snapshot to match the updated defaultMessage format.

🪄 Autofix

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 506e8f93-20a1-4458-a745-0153803a2536

📥 Commits

Reviewing files that changed from the base of the PR and between 6325368 and 62bd69e.

📒 Files selected for processing (1)

• app/components/post_list/post/system_message/system_message.tsx

[Akanshagore]

/check-cla

[Akanshagore]

Hi team, the requested changes have been addressed and CodeRabbit has approved the PR. CLA is also authorized. Could a maintainer please review and approve when available, and approve the pending workflows if needed? This would help unblock the merge. Thanks!

[Akanshagore]

Hi team, just following up on this PR as it’s been a week since my last update. The requested changes have been addressed, CodeRabbit has approved the PR, and the CLA is authorized.

The remaining workflows are still awaiting maintainer approval, and the PR is also waiting for the required reviews. Whenever someone has a chance, could you please take a look and help unblock the PR?

Thanks!

[Akanshagore]

Hi team, just following up on this PR.

The requested changes have been addressed, CodeRabbit has approved the changes, and the CLA is authorized. At the moment, the PR is only blocked on the required maintainer reviews and the pending workflow approvals.

When someone gets a chance, could you please review the PR and approve the pending workflows? It would be really helpful in getting this PR unblocked.

Thanks for your time and support!

[matthewbirtch]

The jira ticket referenced here dosn't seem like the right one @Akanshagore. Could you share the correct Jira ticket and update the PR description?

[matthewbirtch]

Thanks for this @Akanshagore. Looks good to me.

[Willyfrog]

HI @Akanshagore thanks a lot for contributing. I'd like to address some issues more related to our PR process than to the code itself:

• Can you update to the right ticket? MM-26917 is not related to your change
• Can you add a screenshot that shows the change you have implemented?