Test scaling SNARK infrastructure to full security parameters

## Why

The SNARK infrastructure has only been exercised with small protocol parameters (`k = 5`, `m = 100`), while the full security parameters of the network (`k = 1944`, `m = 16948`) require the production circuit tier: around 70 GB of RAM, minutes of proving time, an 800 MB SRS, and a proving key of several GB. Nothing tells us today whether a deployed aggregator can hold that and still produce its certificates in time.

## What

Deploy a SNARK follower aggregator on `testing-preview` with the full security parameters and measure whether the infrastructure scales.

## How

- [ ] Use the sizing of machine for the production circuit tier (see https://github.com/IntersectMBO/mithril/issues/2860#issuecomment-3714830510)
- [ ] Create a SNARK follower on `testing-preview` which runs full parameters
- [ ] Make sure the signers of the network produce SNARK single signatures
- [ ] Measure the setup and proving times, the memory and the disk usage over several epochs
- [ ] Compare the proving time with the duration of a signing round
- [ ] Report the results and document the hardware requirements of a SNARK aggregator