Add JCE Cipher RSA/ECB/OAEPWithSHA-256AndMGF1Padding support

[cconlon]

This PR adds Cipher RSA/ECB/OAEPWithSHA-256AndMGF1Padding support to wolfJCE.

• Implements OAEP encrypt/decrypt via wc_RsaPublicEncrypt_ex()/wc_RsaPrivateDecrypt_ex()
• Add FeatureDetect.RsaOaepEnabled() detection
• Add JUnit tests for testing and regression

ZD 21062

[Copilot]

Pull request overview

This PR adds support for RSA OAEP (Optimal Asymmetric Encryption Padding) encryption with SHA-256 hash and MGF1 padding to wolfJCE. The implementation enables the cipher algorithm RSA/ECB/OAEPWithSHA-256AndMGF1Padding with proper interoperability with standard JCE providers.

Changes:

• Adds native JNI bindings for wc_RsaPublicEncrypt_ex() and wc_RsaPrivateDecrypt_ex() to support OAEP operations
• Implements Java wrapper methods encryptOaep() and decryptOaep() in the Rsa class with proper validation
• Adds comprehensive test suite with 18 test cases covering basic operations, edge cases, error handling, and interoperability

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/test/java/com/wolfssl/provider/jce/test/WolfCryptCipherRSAOAEPTest.java	New comprehensive test suite with 18 test cases for OAEP functionality including basic operations, error handling, and interoperability tests
src/test/java/com/wolfssl/provider/jce/test/WolfJCETestSuite.java	Registers new OAEP test class in test suite
src/main/java/com/wolfssl/wolfcrypt/Rsa.java	Adds encryptOaep/decryptOaep methods with parameter validation and synchronization
src/main/java/com/wolfssl/wolfcrypt/FeatureDetect.java	Adds RsaOaepEnabled() method for runtime feature detection
src/main/java/com/wolfssl/provider/jce/WolfCryptProvider.java	Registers OAEP cipher with conditional compilation check
src/main/java/com/wolfssl/provider/jce/WolfCryptCipher.java	Implements OAEP padding type with proper encryption/decryption routing and error handling
jni/jni_rsa.c	Implements JNI wrappers for wc_RsaPublicEncrypt_ex and wc_RsaPrivateDecrypt_ex with proper resource management
jni/jni_feature_detect.c	Implements RsaOaepEnabled detection using WC_NO_RSA_OAEP macro
jni/include/com_wolfssl_wolfcrypt_Rsa.h	Adds JNI function declarations for OAEP operations
jni/include/com_wolfssl_wolfcrypt_FeatureDetect.h	Adds JNI function declaration for RsaOaepEnabled
README_JCE.md	Documents new cipher algorithm and alias in supported algorithms list

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