fix: ffi wallet file for unknown type name (#4589)

Description
---
Wallet.h file complains of `unknown type` this is a fix for that.

base_layer/wallet_ffi/build.rs

@@ -17,7 +17,7 @@ fn main() {
         parse: ParseConfig {
             parse_deps: true,
             include: Some(vec![
-                // "tari_core".to_string(),
+                "tari_core".to_string(),
                 "tari_common_types".to_string(),
                 "tari_crypto".to_string(),
                 "tari_p2p".to_string(),

base_layer/wallet_ffi/wallet.h

@@ -8,6 +8,11 @@
 #include <stdint.h>
 #include <stdlib.h>
 
+/**
+ * The number of unique fields available. This always matches the number of variants in `OutputField`.
+ */
+#define OutputFields_NUM_FIELDS 10
+
 enum TariTypeTag {
   Text = 0,
   Utxo = 1,
@@ -60,14 +65,28 @@ struct Contact;
 
 struct ContactsLivenessData;
 
+struct Covenant;
+
 struct EmojiSet;
 
+/**
+ * value: u64 + tag: [u8; 16]
+ */
+struct EncryptedValue;
+
+struct FeePerGramStat;
+
 struct FeePerGramStatsResponse;
 
 struct InboundTransaction;
 
 struct OutboundTransaction;
 
+/**
+ * Options for UTXO's
+ */
+struct OutputFeatures;
+
 /**
  * Configuration for a comms node
  */
@@ -138,6 +157,15 @@ struct TariSeedWords;
 
 struct TariWallet;
 
+/**
+ * The transaction kernel tracks the excess for a given transaction. For an explanation of what the excess is, and
+ * why it is necessary, refer to the
+ * [Mimblewimble TLU post](https://tlu.tarilabs.com/protocols/mimblewimble-1/sources/PITCHME.link.html?highlight=mimblewimble#mimblewimble).
+ * The kernel also tracks other transaction metadata, such as the lock height for the transaction (i.e. the earliest
+ * this transaction can be mined) and the transaction fee, in cleartext.
+ */
+struct TransactionKernel;
+
 struct TransactionSendStatus;
 
 struct TransportConfig;
@@ -157,7 +185,7 @@ struct TariCoinPreview {
   uint64_t fee;
 };
 
-typedef TransactionKernel TariTransactionKernel;
+typedef struct TransactionKernel TariTransactionKernel;
 
 /**
  * Define the explicit Public key implementation for the Tari base layer
@@ -261,11 +289,11 @@ typedef RistrettoComSig ComSignature;
 
 typedef ComSignature TariCommitmentSignature;
 
-typedef Covenant TariCovenant;
+typedef struct Covenant TariCovenant;
 
-typedef EncryptedValue TariEncryptedValue;
+typedef struct EncryptedValue TariEncryptedValue;
 
-typedef OutputFeatures TariOutputFeatures;
+typedef struct OutputFeatures TariOutputFeatures;
 
 typedef struct Contact TariContact;
 
@@ -287,7 +315,7 @@ typedef struct Balance TariBalance;
 
 typedef struct FeePerGramStatsResponse TariFeePerGramStats;
 
-typedef FeePerGramStat TariFeePerGramStat;
+typedef struct FeePerGramStat TariFeePerGramStat;
 
 struct TariUtxo {
   const char *commitment;