feat(registry): add HPKE (RFC 9180) to Cryptography Registry (#766)

As discussed in ticket #765, this PR adds HPKE (RFC 9180) to the
Cryptography Registry.

Fixes #765

Details
- Adds the HPKE algorithm family with pattern
`HPKE[-{mode}]-{kem}-{kdf}-{aead}` (primitive: `pke`).
- Adds RFC 9180 as the authoritative reference.
- Updates the registry schema enum to allow `HPKE`.

Scope
- Registry-only (`schema/cryptography-defs.json`) plus corresponding
registry schema update (`schema/cryptography-defs.schema.json`).
- No CycloneDX specification behavior changes.

Author: stevespringett

schema/cryptography-defs.json

@@ -123,6 +123,21 @@
         }
       ]
     },   
+    {
+      "family": "HPKE",
+      "standard": [
+        {
+          "name": "RFC9180",
+          "url": "https://doi.org/10.17487/RFC9180"
+        }
+      ],
+      "variant": [
+        {
+          "pattern": "HPKE[-(mode_base|mode_psk|mode_auth|mode_auth_psk)]-{kem}-{kdf}-{aead}",
+          "primitive": "pke"
+        }
+      ]
+    },
     {
       "family": "MQV",
       "standard": [