Add max-overload mode to generate protocol/model WithResponse overloads for Java data-plane clients

[Copilot]

This change adds explicit control over max WithResponse overload generation in the Java emitter/generator. It supports generating protocol (BinaryData), model, or both overload sets, while preserving Java overload legality by falling back to protocol when signatures differ only by return type.

• Config surface

  • Added @typespec/http-client-java.max-overload emitter option with values:
    • protocol (default)
    • model
    • all

• Generator settings + mode plumbing

  • Added MaxOverload enum and parsing in JavaSettings.
  • Exposed mode helpers (isGenerateProtocolMaxOverload, isGenerateModelMaxOverload) for mapper/template logic.

• WithResponse overload generation behavior

  • Updated simple WithResponse mapping for data-plane clients:
    • protocol: generate protocol-style max overloads only.
    • model: generate model max overloads (using RequestOptions) and suppress public protocol overload exposure where model API exists.
    • all: generate both, except when Java signature collision would occur.

• Collision handling for all

  • Added signature-collision filtering in convenience-method wiring:
    • If protocol/model WithResponse overloads normalize to the same public signature (name + params), model overload is dropped.
    • This preserves existing protocol behavior and avoids illegal return-type-only overloading.

• Convenience template alignment

  • Updated convenience method templates to handle RequestOptions parameterized model max overloads (null-safe initialization when passed in vs local creation).
  • Kept protocol method invocation wiring intact across sync/async wrappers.

• Focused test coverage updates

  • Added mapper-level tests for protocol / model / all visibility behavior.
  • Added small test-only settings helpers to configure JavaSettings modes deterministically.

"@azure-tools/typespec-java":
  flavor: azure
  max-overload: all

public Response<BinaryData> createFooWithResponse(BinaryData createFooOptions, RequestOptions requestOptions);
public Response<FooDetails> createFooWithResponse(CreateFooOptions createFooOptions, RequestOptions requestOptions);

Warning

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I tried to connect to the following addresses, but was blocked by firewall rules:

• archive.eclipse.org
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.14/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.14/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.14 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.14/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/typespec/typespec/packages/http-client-java/generator org.codehaus.plexus.classworlds.launcher.Launcher -pl http-client-generator-core spotless:apply (dns block)

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