Add JCE support for HmacSHA3 KeyGenerator

[cconlon]

This PR implements HmacSHA3 variant support in KeyGenerator. We already had HmacSHA3 support in the Mac class, but not yet in KeyGenerator:

KeyGenerator:
- HmacSHA3-224
- HmacSHA3-256
- HmacSHA3-384
- HmacSHA3-512

JUnit tests are included here for regression. This fixes the OpenJDK SunJCE test: crypto/provider/Mac/MacKAT.java

[Copilot]

Pull Request Overview

This PR adds support for HmacSHA3 key generation variants to the JCE provider, extending the existing HmacSHA3 support that was already available in the Mac class to include KeyGenerator functionality.

• Adds four new HmacSHA3 algorithm types (224, 256, 384, 512) to the KeyGenerator enum and implementation
• Registers new KeyGenerator classes for each HmacSHA3 variant in the WolfCryptProvider
• Includes comprehensive JUnit tests with feature detection to ensure compatibility with native wolfSSL builds

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
WolfCryptKeyGenerator.java	Implements HmacSHA3 algorithm support with new enum values and KeyGenerator classes
WolfCryptProvider.java	Registers the new HmacSHA3 KeyGenerator implementations with feature detection
WolfCryptKeyGeneratorTest.java	Adds comprehensive test coverage for all four HmacSHA3 variants
README_JCE.md	Documents the newly supported HmacSHA3 KeyGenerator algorithms

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