## Summary
`Rectangle3DConverter.Write` corrupts a rectangle's Z range for certain bounds. The omit-z guard was:
```csharp
var writeZ = value.Start.Z is > sbyte.MinValue and < sbyte.MaxValue
|| value.End.Z is > sbyte.MinValue and < sbyte.MaxValue;
```
This drops `z1`/`z2` whenever **both** Z bounds sit at/outside the sbyte extremes — but `Read` reconstructs absent Z as exactly `z1 = -128, z2 = 127` (depth 255). So any rectangle that trips the omit condition without *being* that sentinel round-trips to depth 255 and is corrupted.
The concrete case: a **homeRange-style** bound `Start.Z = -128, End.Z = 128` (depth 256, the full vertical range used by spawners) gets `z1`/`z2` omitted on write, then reads back as depth **255** — silently losing the top z-level on every re-serialize.
(Spotted while working on #2505; spawners now prefer the `homeRange` form so most square bounds avoid this path, but any non-square `spawnBounds` or other `Rectangle3D` JSON is affected.)
## Fix
Omit Z only for the exact sentinel `Read` produces (`z1 == -128 && z2 == 127`); write it for anything else:
```csharp
var writeZ = value.Start.Z != sbyte.MinValue || value.End.Z != sbyte.MaxValue;
```
`Read` is unchanged, so existing `regions.json` rectangles that omit Z keep loading identically.
## Tests
New `Rectangle3DConverterTests`: round-trips the homeRange depth-256 case, the depth-255 sentinel, and ordinary/edge z values; asserts the sentinel omits Z while homeRange bounds write it. Server.Tests 717/717, UOContent.Tests 487/487.
### Summary
- Works around a sneaky edge case bug in the JIT with stackalloc where sometimes the buffer is not zero'd.
- Fixes SendDisplayBoatHS
- Fixes sending health bars in the `SendEverything()` logic.
- Fixes a bug in sizing for some string helper functions.
### Developer Note
We are enabled `SkipLocalsInit` - do not rely on `stackalloc` to be zero'd. To zero the buffer, use `span.Clear();`
Closes#1606
## Possible Breaking Change
* Reverted regions.json back to RunUO until newer regions are implemented and proper expansion checks are added.
### Other Changes
- [X] Adds `Region.IsPartOf<T1, T2>()` to check for multiple types.
- [X] Fixes regions.json being wrong
- [X] Adds lots of missing regions. **They are not implemented properly yet**
- [X] Adds regions.xml -> regions.json (check ModernUO Discord)
- [X] Adds expansion specific regions.
**Only one functional change**
* Fixes a bug in LogFactory where `Warning` is being logged as `Information`
Non-functional changes:
* Updates/Fixes copyright headers
* Removes namespace scopes for core files.
View with [whitespace off](https://github.com/modernuo/ModernUO/pull/1187/files?w=1).
