This diagnostic is issued when an operation marked with `@clientLocation` points to a target that is not a valid client location under the root namespace decorated with `@service`.

## Impact

- **Area:** Client operation placement. Generation continues, but the operation cannot be moved to a target outside the valid service client hierarchy.
- **Not affected:** The operation's HTTP route and protocol metadata are unchanged.

## ❌ Incorrect Usage

```typespec
namespace OtherNamespace {

}

@service
namespace MyService {
  @clientLocation(OtherNamespace) // target is outside the `MyService` service namespace
  op list(): void;
}
```

## Diagnostic Message

TCGC reports:

```text
`@clientLocation` could only move operation to the interface or namespace belong to the root namespace with `@service`.
```

## ✅ How to Fix

Move the operation to an interface or namespace that belongs to the root service namespace, or define the intended target as a valid client under that service.

```typespec
@service
namespace MyService {
  namespace Operations {

  }

  @clientLocation(Operations)
  op list(): void;
}
```

## Suppression

This diagnostic should not be suppressed. Move the operation to an interface or namespace that belongs to the root `@service` namespace.
