Adjust AES-CTS to allow for single block operation

[cconlon]

This PR adds AES-CTS support for one block (16-byte) input, and fixes buffering behavior.

• Support exactly 16-byte inputs per RFC 3962/8009 (reduces to plain CBC)
• Change CTS to buffer all data until doFinal() instead of streaming
  • CTS requires the entire message for ciphertext stealing
  • Groups CTS with GCM/CCM as non-streaming modes
• Add tests for 16-byte edge case (byte array and ByteBuffer)
• Update existing tests to reflect correct buffering behavior

This fixes SunJCE KerberosAesSha2 test failures when using AES-CTS encryption with exactly one block of input.

[Copilot]

Pull Request Overview

This PR adds AES-CTS support for exactly 16-byte (single block) inputs and corrects the buffering behavior to ensure CTS processes the entire message at finalization rather than streaming incrementally.

• Updates minimum input length requirement from > 16 bytes to >= 16 bytes per RFC 3962/8009
• Changes CTS buffering to match GCM/CCM: buffer all data until doFinal() call
• Implements single-block edge case in JNI using plain CBC encryption/decryption
• Adds comprehensive test coverage for 16-byte inputs using both byte arrays and ByteBuffers

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/main/java/com/wolfssl/wolfcrypt/AesCts.java	Updated validation logic from <= BLOCK_SIZE to < BLOCK_SIZE and revised documentation to reflect that CTS now accepts exactly 16 bytes
src/main/java/com/wolfssl/provider/jce/WolfCryptCipher.java	Added CTS to non-streaming modes (with GCM/CCM) in isNoOpUpdate(), removed CTS from streaming cipher list, updated minimum length validation, and added explanatory comments
src/test/java/com/wolfssl/wolfcrypt/test/AesCtsTest.java	Updated test to verify 15-byte rejection and 16-byte acceptance, replaced hard-coded values with Aes.BLOCK_SIZE constant
src/test/java/com/wolfssl/provider/jce/test/WolfCryptCipherTest.java	Added 16 to test data sizes, updated minimum length test to verify 15-byte rejection and 16-byte acceptance, added two new comprehensive tests for single-block edge case (byte array and ByteBuffer paths)
jni/jni_aescts.c	Updated validation from <= AES_BLOCK_SIZE to < AES_BLOCK_SIZE, added special case handling for exactly 16 bytes using plain CBC (applies to both byte array and ByteBuffer JNI methods)

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