We should make more use of `FrozenDictionary` and `FrozenSet`

[ElectroJr]

• [ ] Look into replacing NetSerializer's TypeDictionary with a FrozenDictionary.
  • Nontrivial, and will require benchmarking
• [x] Replace dictionaries in yaml prototypes
  • Should be trivial after a type serializer gets added.
• [x] yaml serialization methods.
• [ ] Maybe replace some dictionary caches with frozen dictionaries? E.g., IReflectionManager's TryParseEnumReference?
  • Would require discovering & adding cached values on startup to avoid unnecessary freezing
• [ ] Linguini? Might require changing the nuget into a submodule
• [ ] Component factory #4726
• [ ] Event bus #4727