PowerShell v7 (7.5.4) mis-handles [Int128] overflow

### Prerequisites

- [x] Write a descriptive title.
- [x] Make sure you are able to repro it on the [latest released version](https://github.com/PowerShell/PowerShell/releases)
- [x] Search the existing issues.
- [x] Refer to the [FAQ](https://github.com/PowerShell/PowerShell/blob/master/docs/FAQ.md).
- [x] Refer to [Differences between Windows PowerShell 5.1 and PowerShell](https://learn.microsoft.com/powershell/scripting/whats-new/differences-from-windows-powershell).

### Steps to reproduce

For [Int32] and [Int64] types, overflow is promoted to [Double] (arguably, should be promoted to longer Int types as [Int16] and [Byte] are).
But for [Int128], overflow results in wrong numbers with no type conversion and no overflow error thrown (arguably should be promoted to [BigInt]).
Positive [Int128] overflows to erroneous result (sometimes less than [Int128]::MaxValue, sometimes negative).
Negative [Int128] sometimes overflows to zero, sometimes to [Int128]::MinValue.
("Easy" fix: promote to [Double] as [Int32] and [Int64].)
Demo code:

```PowerShell
$PSVersionTable
 [Byte]::MaxValue+[Byte]::MaxValue
([Byte]::MaxValue+[Byte]::MaxValue).GetType().Name
 [Int16]::MaxValue+[Int16]::MaxValue
([Int16]::MaxValue+[Int16]::MaxValue).GetType().Name
 [Int32]::MaxValue+[Int32]::MaxValue
([Int32]::MaxValue+[Int32]::MaxValue).GetType().Name
 [Int64]::MaxValue+[Int64]::MaxValue
([Int64]::MaxValue+[Int64]::MaxValue).GetType().Name
 [Int128]::MaxValue+[Int128]::MaxValue
([Int128]::MaxValue+[Int128]::MaxValue).GetType().Name
[Int128]::MaxValue*10
[Int128]::MaxValue
([Int128]::MaxValue/2)*10
[Int128]::MinValue+[Int128]::MinValue
[Int128]::MinValue
[Int128]::MinValue*5
[Int128]::MinValue*-5
[Int128]::MinValue*-10
```
<img width="1920" height="1032" alt="Image" src="https://github.com/user-attachments/assets/e3b4503e-54a3-4346-838a-f7be748e5d6c" />


### Expected behavior

```console
[Int128] overflow converted to [Double] or [BigInt] or overflow error thrown.
```

### Actual behavior

```console
Incorrect mathematical result is returned for [Int128] overflow.
```

### Error details

```console
N/A
```

### Environment data

```powershell
Name                           Value
----                           -----
PSVersion                      7.5.4
PSEdition                      Core
GitCommitId                    7.5.4
OS                             Microsoft Windows 10.0.26200
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0, 5.0, 5.1, 6.0, 7.0}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0
```

### Visuals

(Screenshot in "Steps to reproduce" section.)

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PowerShell v7 (7.5.4) mis-handles [Int128] overflow #26677

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PowerShell v7 (7.5.4) mis-handles [Int128] overflow #26677

Description

Prerequisites

Steps to reproduce

Expected behavior

Actual behavior

Error details

Environment data

Visuals

Metadata

Metadata

Assignees

Labels

Type

Fields

Projects

Milestone

Relationships

Development

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