Adds structures to read/write saved spawner data such as seeds, counts.
Adds generator and validator to emulate the FixInitSpec builder used by the game logic
Similar to SW/SH raids, validating these in-process is not feasible due to the number crunching required.
This does not handle the encounter slot call or the follow-up level range call. Just the inner FixInitSpec ctor & fill.
level is calc'd:
randFloat(sum) -> slot float
rand.Next() -> gen_seed (for all the details)
rand.NextInt(delta) +min -> level
Co-Authored-By: Lusamine <30205550+Lusamine@users.noreply.github.com>