[Bug]: ACU upgrades that add splash damage via `NewDamageRadius` do not enable the splash damage indicator

### Describe the Bug

The Seraphim ACU does not have a splash damage indicator by default. This does not change even if the `Refracting Chronotron Amplifier` enhancement, which adds a significant 2.7 splash radius, is upgraded. Potentially also significant for mod compatibility. The splash damage indicator is handled in `lua/ui/controls/worldview.lua`.

Disclaimer: an exeption would be upgrades like TML. But these are handled differently due to being defined as weapons and being disabled if their respective upgrades are not present.

### Reproduce the bug

See above.

### Screenshots

_No response_

### Additional context

_No response_

Start in lua/ui/controls/worldview.lua, where the splash damage indicator is handled, and reproduce the Seraphim ACU behavior before and after the Refracting Chronotron Amplifier upgrade. Trace how the upgrade's NewDamageRadius value is represented and determine what the indicator needs to recognize it. Done means the ACU shows the correct splash radius after upgrading, while the existing TML behavior remains unaffected.

Written by the indexing model from the issue text.