Wire HAETAE into BCPQC provider

Add JCA/JCE shell around the existing lightweight pqc.crypto.haetae
package: HaetaeParameterSpec, HaetaeKey, BCHaetae{Public,Private}Key,
HaetaeKeyFactorySpi, HaetaeKeyPairGeneratorSpi, SignatureSpi and the
Haetae Mappings class.  HAETAE-2/3/5 are registered under BCPQC and
the three BC-arc OIDs (haetae.{1..3}) are wired through
PublicKeyFactory / PrivateKeyFactory / SubjectPublicKeyInfoFactory /
PrivateKeyInfoFactory.  BouncyCastleProvider.loadPQCKeys() registers
the OIDs so the standard BC provider can decode HAETAE-bearing certs
and PKCS#8 keys.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>