feat(server): add Mobile.SayTo localized overload with explicit hue (#2481)

## Summary

`Mobile.SayTo(Mobile to, int number, string args = "")` always sends the localized message using `SpeechHue`. This adds a parallel overload that accepts an explicit `hue`:

```csharp
public void SayTo(Mobile to, int number, int hue, string args = "") =>
    to.NetState.SendMessageLocalized(Serial, Body, MessageType.Regular, hue, 3, number, Name, args);
```

It mirrors the existing localized overload exactly, only substituting the caller-provided `hue` for `SpeechHue`, so content can send a cliloc message to a single mobile in a chosen color without dropping down to `NetState.SendMessageLocalized` directly. This restores the hued-cliloc `SayTo` that RunUO/ServUO content commonly relied on (e.g. `SayTo(from, 1042205, 0x3B2)`).

## Notes
- Purely additive; no behavior change to existing call sites.
- No overload ambiguity: `SayTo(m, num)` and `SayTo(m, num, "args")` still bind to the existing overload; `SayTo(m, num, hue)` binds to the new one (the third positional arg is `int` vs `string`).
- Null-safe to the same degree as the existing overload (`SendMessageLocalized` guards via `CannotSendPackets()`).

## Test Plan
- [x] `dotnet build Projects/Server` — 0 warnings, 0 errors.
- One-line additive overload mirroring an existing (untested) method; no existing `Mobile.SayTo` unit tests to extend. Happy to add coverage if preferred.

Projects/Server/Mobiles/Mobile.cs

@@ -8132,6 +8132,9 @@ public partial class Mobile : IHued, IComparable<Mobile>, ISpawnable, IObjectPro
     public void SayTo(Mobile to, int number, string args = "") =>
         to.NetState.SendMessageLocalized(Serial, Body, MessageType.Regular, SpeechHue, 3, number, Name, args);
 
+    public void SayTo(Mobile to, int number, int hue, string args = "") =>
+        to.NetState.SendMessageLocalized(Serial, Body, MessageType.Regular, hue, 3, number, Name, args);
+
     public bool SendHuePicker(HuePicker p)
     {
         if (m_NetState != null)