Honor exact C# names over back-compat naming

[Copilot]

Names explicitly configured with exact could be replaced by names restored from the previous contract. This made advanced client naming overrides ineffective when back compatibility was enabled.

• Naming precedence

  • Preserve exact names for service parameters and property-derived model factory parameters.
  • Continue restoring last-contract names for non-exact parameters.

• Model factories

  • Treat exact-name-only differences as compatible signatures.
  • Avoid generating duplicate back-compat overloads.

• Coverage

  • Add regression cases for RestClient and model factory naming paths.

@clientName(Azure.ClientGenerator.Core.exact("api_key"), "csharp")
apiKey: string;

The generated C# parameter remains api_key, even when the previous contract used another name.

• Fixes Consider Having Exact Override Back Compat Naming #11640

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npm i https://pkg.pr.new/@typespec/http-client-csharp@11663

commit: f86f70e

[Copilot]

Pull request overview

Ensures exact C# parameter names take precedence over names restored from previous contracts.

Changes:

• Skips back-compat renaming for exact service and property-derived parameters.
• Prevents duplicate model factory compatibility overloads.
• Adds regression tests for RestClient and model factory paths.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
.../test/Providers/TypeProviderTests.cs	Tests exact-name precedence.
.../BuildMethodsForBackCompatibilityExactNameTakesPrecedence(Last)/TestClient.cs	Defines the prior contract fixture.
.../BuildMethodsForBackCompatibilityExactNameTakesPrecedence.cs	Captures expected exact-name output.
.../BackCompatibility_ExactPropertyNameTakesPrecedence(Last)/SampleNamespaceModelFactory.cs	Defines the prior model factory contract.
.../BackCompatibility_ExactPropertyNameTakesPrecedence.cs	Captures expected model factory output.
.../ModelFactoryProviderTests.cs	Tests mixed exact and restored property names.
.../Utilities/BackCompatHelper.cs	Excludes exact parameters from name restoration.
.../Providers/ParameterProvider.cs	Exposes exact-name metadata for parameters.
.../Providers/ModelFactoryProvider.cs	Treats exact-name differences as compatible.
.../ExactParameterNameTakesPrecedenceOverLastContractView(Last)/TestClient.cs	Defines the prior RestClient contract.
.../ExactParameterNameTakesPrecedenceOverLastContractView.cs	Captures expected RestClient output.
.../RestClientProviderTests.cs	Adds RestClient naming regression coverage.
.../RestClientProvider.cs	Prevents last-contract names overriding exact names.

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[Jorge Rangel (jorgerangel-msft)]

Copilot pull latest from main and address the merge conflicts

[Copilot]

Pull request overview

Copilot reviewed 24 out of 24 changed files in this pull request and generated no new comments.

[Copilot]

Copilot pull latest from main and address the merge conflicts

Merged the latest main and resolved the overlapping model-provider test conflict in merge commit 73521eaa8, retaining both regressions.