bip138: exclude roots exposed by another expression

A root selected through a derived xpub can also appear bare or as a
literal key. Once a spend reveals it, anyone could decrypt the backup.
Exclude such cases.

bip-0138/test_vectors/recipient_keys.json

@@ -103,5 +103,29 @@
       "8b42cd4776376c82791b494155151f56c2d7b471e0c7a526a7ce60dd872e3867",
       "ebd252ca0877aae09b9d058219682775aa3cbcd049c12f07832f2cf6a3b51708"
     ]
+  },
+  {
+    "description": "Root used both bare and derived is excluded",
+    "descriptors": [
+      "wsh(or_i(pk(tpubDEPBvXvhta3pjVaKokqC3eeMQnszj9ehFaA2zD5nSdkaccwGAizu8jVB2NeSpvmP2P52MBoZvNCixqXRJnTyXx51FQzARR63tjxQSyP3Btw/0/*),pk(tpubDEPBvXvhta3pjVaKokqC3eeMQnszj9ehFaA2zD5nSdkaccwGAizu8jVB2NeSpvmP2P52MBoZvNCixqXRJnTyXx51FQzARR63tjxQSyP3Btw)))"
+    ],
+    "expected_keys": null
+  },
+  {
+    "description": "Xpub root (03ebd252ca0877aae09b9d058219682775aa3cbcd049c12f07832f2cf6a3b51708) excluded by an opposite-parity literal in another descriptor set",
+    "descriptors": [
+      "tr(tpubDEPBvXvhta3pjVaKokqC3eeMQnszj9ehFaA2zD5nSdkaccwGAizu8jVB2NeSpvmP2P52MBoZvNCixqXRJnTyXx51FQzARR63tjxQSyP3Btw/*)",
+      "wpkh(02ebd252ca0877aae09b9d058219682775aa3cbcd049c12f07832f2cf6a3b51708)"
+    ],
+    "expected_keys": null
+  },
+  {
+    "description": "MuSig participant exposed in a script leaf",
+    "descriptors": [
+      "tr(musig(tpubDC5FSnBiZDMmhiuCmWAYsLwgLYrrT9rAqvTySfuCCrgsWz8wxMXUS9Tb9iVMvcRbvFcAHGkMD5Kx8koh4GquNGNTfohfk7pgjhaPCdXpoba,tpubDEPBvXvhta3pjVaKokqC3eeMQnszj9ehFaA2zD5nSdkaccwGAizu8jVB2NeSpvmP2P52MBoZvNCixqXRJnTyXx51FQzARR63tjxQSyP3Btw)/0/*,pk(tpubDC5FSnBiZDMmhiuCmWAYsLwgLYrrT9rAqvTySfuCCrgsWz8wxMXUS9Tb9iVMvcRbvFcAHGkMD5Kx8koh4GquNGNTfohfk7pgjhaPCdXpoba))"
+    ],
+    "expected_keys": [
+      "ebd252ca0877aae09b9d058219682775aa3cbcd049c12f07832f2cf6a3b51708"
+    ]
   }
 ]