Documentation fix for UnifiedAddressForReciever (+ spelling corrections.)

src/wallet/wallet.h

@@ -2117,6 +2117,11 @@ public:
 };
 
 // UnifiedAddressForReceiver :: (CWallet&, Receiver) -> std::optional<UnifiedAddress>
+//
+// When this visitor returns `std::nullopt` it means that either the receiver is not
+// recognized as belonging to any key known to the wallet, or that the receiver
+// is an internal change receiver for which it is not permitted to generate a
+// unified address per ZIP 315.
 class UnifiedAddressForReceiver {
 private:
     const CWallet& wallet;

src/zcash/address/orchard.hpp

@@ -211,7 +211,7 @@ public:
     /**
      * Extracts the diversifier from the specified address and decrypts it as
      * a diversifier index, then verifies that this diversifier index produces
-     * the same address. This method attempts decrypion using both the internal
+     * the same address. This method attempts decryption using both the internal
      * and external parts of the full viewing key.
      *
      * Returns a pair consisting of the diversifier index and a flag indicating

src/zcash/address/zip32.h

@@ -187,7 +187,7 @@ public:
     /**
      * Extracts the diversifier from the specified address and decrypts it as
      * a diversifier index, then verifies that this diversifier index produces
-     * the same address. This method attempts decrypion using both the internal
+     * the same address. This method attempts decryption using both the internal
      * and external parts of the full viewing key.
      *
      * Returns a pair consisting of the diversifier index and a flag indicating