Add click+hold rapid-fire functionality for GhostStructures

**Is your feature request related to a problem? Please describe.**
As discussed in #5265

> I felt the UI of cycling between 5x=>10x=>50x etc was a bit clunky. I'm wondering if there could be another way to launch many nukes, like click and hold for example

_Originally posted by @evanpelle in [#5265](https://github.com/openfrontio/OpenFrontIO/issues/5265#issuecomment-5576184189)_

**Describe the solution you'd like**
A non-buggy implementation of the [prototype](https://github.com/openfrontio/OpenFrontIO/pull/5280) that is readable (as of 10/9/2026 I have working and clean code 😊)

**Describe alternatives you've considered**
I've considered whether or not this functionality or one similar to it should/could carry over into the mobile version.

**Assignment**

- [x] I'd like to be assigned to this issue and work on it myself