First pass Fenrir fixes

[cconlon]

Summary

This PR fixes 19 JNI/JCE issues identified by Fenrir, and adds some missing JUnit test coverage for Ed25519, Curve25519, RSA PKCS8 decode, RSA CRT export, and HMAC offset/length validation.

• wc_ed25519_verify_msg() was passed message length instead of signature length
• RsaFlattenPublicKey() and RsaExportCrtKey() cast 64-bit jlong* to 32-bit word32* for size parameters
• wc_RsaEncryptSize() return assigned to unsigned word32 then checked < 0 (always false) in 8 RSA functions
• HMAC throwWolfCryptExceptionFromError(env, ret) passed ret (still 0) instead of hmacSz
• Add HMAC offset/length validation against array size in both byte array and ByteBuffer variants
• NULL check improvements for HMAC, Ed25519, Curve25519, Pwdbased
• More aggressive local reference cleanup
• Return defensive copy of IV array for AES-GCM engineGetIV()

[Copilot]

Pull request overview

Addresses Fenrir-reported JNI/JCE issues across RSA, HMAC, Ed25519, Curve25519, and related native bindings, and expands JUnit coverage for key crypto workflows and edge cases.

Changes:

• Fixes JNI argument handling/size conversions for RSA and corrects Ed25519 verify parameter usage.
• Adds stronger bounds validation and improved cleanup (local refs / pinned arrays) in several JNI modules.
• Adds/extends JUnit tests for Ed25519, Curve25519, RSA PKCS8 + raw export sizing, and HMAC offset/length behavior.

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 14 comments.

Show a summary per file

File	Description
src/test/java/com/wolfssl/wolfcrypt/test/WolfCryptTestSuite.java	Adds Ed25519/Curve25519 tests to the suite.
src/test/java/com/wolfssl/wolfcrypt/test/RsaTest.java	Adds PKCS8 decode/verify and raw export sizing tests.
src/test/java/com/wolfssl/wolfcrypt/test/HmacTest.java	Adds tests for offset/length validation and ByteBuffer updates.
src/test/java/com/wolfssl/wolfcrypt/test/Ed25519Test.java	New JUnit coverage for Ed25519 sign/verify/export/import.
src/test/java/com/wolfssl/wolfcrypt/test/Curve25519Test.java	New JUnit coverage for Curve25519 shared secret and export/import.
src/main/java/com/wolfssl/wolfcrypt/Ed25519.java	Exposes Ed25519 key/signature sizes as Java constants.
src/main/java/com/wolfssl/wolfcrypt/Curve25519.java	Exposes Curve25519 key size as a Java constant.
src/main/java/com/wolfssl/provider/jce/WolfCryptCipher.java	Returns defensive copy of IV from engineGetIV().
jni/jni_rsa.c	Fixes size type handling, cleanup, and encrypt-size checks in RSA JNI.
jni/jni_pwdbased.c	Avoids dereferencing NULL Java arrays when pinning password/salt buffers.
jni/jni_hmac.c	Adds offset/length bounds validation and fixes error propagation in final.
jni/jni_fips.c	Ensures pinned IV array is released on BAD_FUNC_ARG path.
jni/jni_ed25519.c	Improves NULL checks, removes stray printf, fixes sig length lookup.
jni/jni_ecc.c	Adds missing releases for pinned parameter arrays.
jni/jni_curve25519.c	Improves NULL checks and streamlines error handling for Curve25519 JNI.
jni/jni_chacha.c	Ensures pinned input is released on error and on success.
jni/include/com_wolfssl_wolfcrypt_Ed25519.h	Exposes Ed25519 size constants to JNI header.
jni/include/com_wolfssl_wolfcrypt_Curve25519.h	Exposes Curve25519 key size constant to JNI header.

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