[azure-http-specs] Add !javascript scope to @OverRide decorator for GroupParameters.group (#3389)

- [x] Understand the current state and verify the file structure
- [x] Update line 29 in client.tsp to add "!javascript" scope parameter
- [x] Format code with Prettier
- [x] Add changeset using chronus
- [x] Test the changes to ensure they work correctly
- [x] Verify no other related changes are needed

## Summary

Updated the `@override` decorator for `GroupParameters.group` operation
in
`/packages/azure-http-specs/specs/azure/client-generator-core/override/client.tsp`
to add the `"!javascript"` scope parameter. This excludes JavaScript
emitters from this override customization.

### Changes Made:
1. Changed line 29 to add `"!javascript"` scope parameter
2. Formatted the code with Prettier to follow multiline style
3. Added a changeset for the azure-http-specs package

### Final Code:
```typespec
@@OverRide(_Specs_.Azure.ClientGenerator.Core.Override.GroupParameters.group,
  groupCustomized,
  "!javascript"
);
```

### Verification:
- ✅ Full build successful
- ✅ All typespec-client-generator-core tests pass (992 tests)
- ✅ All scenario validations pass (58 full scenarios, 40 scenarios)
- ✅ Code formatted with Prettier
- ✅ Changeset added using chronus

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<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>[JS] @OverRide group is not supported yet.</issue_title>
> <issue_description>Update
https://github.com/Azure/typespec-azure/blob/main/packages/azure-http-specs/specs/azure/client-generator-core/override/client.tsp#L29
> to
`@@OverRide(_Specs_.Azure.ClientGenerator.Core.Override.GroupParameters.group,
groupCustomized, "!javascript");`</issue_description>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>

Fixes #3388

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Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: v-jiaodi <[email protected]>

Author: Copilot

.chronus/changes/copilot-update-override-group-support-2025-9-14-8-52-1.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@azure-tools/azure-http-specs"
+---
+
+Add !javascript scope to @override decorator for GroupParameters.group

packages/azure-http-specs/specs/azure/client-generator-core/override/client.tsp

@@ -26,7 +26,10 @@ model GroupParametersOptions {
 
 op groupCustomized(options: GroupParametersOptions): void;
 
-@@override(_Specs_.Azure.ClientGenerator.Core.Override.GroupParameters.group, groupCustomized);
+@@override(_Specs_.Azure.ClientGenerator.Core.Override.GroupParameters.group,
+  groupCustomized,
+  "!javascript"
+);
 
 op requireOptionalCustomized(@path param1: string, @path param2: string): void;