Extend preinitialization interpreter (#92470)

Things that I added:

* Support for `typeof(T) == typeof(Bar)` (this will be useful later, we'll eventually be able to also freeze these).
* Support static interface method calls
* Constrained method calls on valuetypes
* More `ReadOnlySpan` construction patterns, `.Length`
* More indirect load/store support

Contributes to #78681. To full resolve this, we need to fix up things so we can answer `Sse2.IsSupported`.