style(sig): Inbox list chrome cleanup

[Twixes]

Changes

1. Removing this extra scan line loader, which was for indicating continuous refresh, but is redundant vs. the red dot.

1. All of the below was selectable text like browser content, but in a desktop app that's wrong - only dynamic content should be selectable with a text cursor.

[Twixes]

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• feat(sig): Make report list toolbar always-on #1532
• feat(sig): Inbox toolbar #1531
• style(sig): Inbox list chrome cleanup #1530 👈 (View in Graphite)
• feat(sig): add modifying report state via inbox #1513
• feat(sig): break inbox into some components #1505
• main

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