Improve runner status icon usability and a11y

What does this MR do?

Fixes runner icons as per #294246 (closed).

This MR updates the runner icons to make their size unform and improve their accesibility and localization.

Why work on this? Shouldn't this just be done in Vue?

I planned to remove some CSS to reduce our ~"technical debt", but in the process I found that before migrating to Vue, as an intermediate step improve their appearance and have an easy migration later.

Screenshots (strongly suggested)

Before	After

New tooltips! 🛠

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
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Security

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Related to #294246 (closed)