Show archive icon for archived channels and add test (fixes #1992)

[nsamuelreddy]

This PR updates the channel list to display an archive SVG icon for channels marked as archived.

Changes:

• Shows the archive icon for archived channels and the normal icon for others
• Registers the SVG asset in pubspec.yaml and places it in assets/icons/archive.svg
• Adds a widget test to verify the archive icon appears for archived channels and a normal icon for non-archived channels

Testing:

• Ran the new widget test to confirm correct icon display

Fixes #1992

[gnprice]

This PR makes a large number of extraneous changes. Please see our contributor guidelines, and revise this as best you can to be a highly reviewable PR with clear and coherent commits.

[nsamuelreddy]

Thanks for pointing this out. I see that the PR currently contains unrelated and generated changes. I’ll reset the branch, reapply only the archived-channel icon change, and split it into clean, reviewable commits following the contributor guidelines. I’ll post an update once done.

[nsamuelreddy]

Thanks! I’ve cleaned up the branch, removed the unrelated changes, and kept the PR focused on the archived-channel icon and its test. All checks are passing and the branch is now up to date.
Please let me know if any further adjustments are needed.