* Removes scaled speed by dex for monsters
* Changes scaled speed by dex for pets (HS+ expansion) to be 400ms -> 100ms between 50 -> 200 dex
* Removes speed changes that were broken for various mobs
* Combines "Legacy" speed and renames the class to `NPCSpeeds`
* Creates speed "classes" (slow, medium, fast, very fast)
* Introduces a new overridable property `SpeedClass`. Register a new speed class using `NPCSpeeds.Register()` and then set the speed class to bulk/mass apply speeds.
Order of speed determination:
1. SpeedMod
2. SpeedClass property (not null)
3. SpeedClass entry in Data\npc-speeds.json for that type
4. "Fast" (200ms Active, 400ms Passive)
* Introduces `RawInterpolatedStringHandler` which is exactly the same as `DefaultInterpolatedStringHandler` except it _unsafely exposes_ it's `ReadOnlySpan<char>` buffer. This is useful for writing the string's data without actually building the string.
* Uses this new string interpolation handler in `SpanWriter` to eliminate intermediate strings built. This is immensely useful in eliminating string allocations in writing Gump packets.
* Changes reading multi.mul/multi.idx so it is loaded entirely during bootup.
* Fixes finding files in Linux.
* Fixes handling HS format.
* Removes verdata support.
ModernUO will still have issues if there is a multi.mul that is pre-HS loaded when it detects a client that is 7.0.9+.
Adds. Gen2Callback for STArrayPool so it can purge the internal array stacks properly. This only happens if significant timed has passed, 2 Gen 2's have been run, and memory pressure exceeds a threshold.
Changes gump compilation to use string interpolation. .NET 6 uses code generation and compile time tricks to speed up string interpolation between 15 and 30% and reduce allocations dramatically.
## Added Feature
Adds a single threaded array pool that works exactly the same as `ArrayPool<T>.Shared`.
The `STArrayPool<T>.Shared` can only be used on a single thread, the main game thread of the server.
Note: Unlike the built-in array pool, there is no hook into the _GC Gen 2_. This means to relieve potentially high memory pressure, `ArrayPool<T>.Shared.Trim()` must be called. The pool will only release arrays _after two successive calls within 10 seconds or longer_. If the server is at less than 70% total memory usage, or the server is not going to use this pool for something egregious, then don't bother ever calling Trim().
## Changes
- [X] Fixes ArrayPool calls that should be cleared due to references.
- [X] Benchmarks against ArrayPool with 4+ rented arrays deep of the same length.
- [x] Unit tests
- [X] Removes static freezing/unfreezing. Use other tools for this.
- [X] Cleans up IPoint3D allocations
- [X] Removes IPoint3D constructors since the compiler may not optimize the constructor path and allow allocations.
Note: Instead of `new Point3D(m)`, do something like `new Point3D(m.Location)`. Sorry for the inconvenience. In the long run this will prevent abuse of hot paths that will cause performance issues.
