fix(java): Fix java wire tests for sdks with oauth

[jsklan]

Description

Fixes several bugs in Java V2 generator affecting wire tests, dynamic snippets, and streaming endpoint support for OAuth-enabled APIs.

Changes Made

• OAuth support: Add withCredentials() pattern for OAuth APIs in dynamic snippets and wire tests instead of using standard builder() pattern
• Streaming endpoints: Fix return type generation to use Iterable<T> instead of incorrectly using Optional<T> for streaming responses
• ArrayList import: Fix missing java.util.ArrayList import when generating empty list literals
• Wire test cleanup: Remove incorrect "Stream" suffix transformation that was adding invalid method names

Testing

• Ran seed generation with custom OAuth project
• Verified ./gradlew compileJava passes
• Verified ./gradlew test passes

[github-actions]

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