Remove uses of fee globals in wallet code

This commit does not change behavior.

src/interfaces/chain.h

@@ -19,6 +19,7 @@ class CScheduler;
 class CTransaction;
 class uint256;
 struct CBlockLocator;
+struct FeeCalculation;
 
 namespace interfaces {
 
@@ -145,6 +146,15 @@ public:
 
     //! Check chain limits.
     virtual bool checkChainLimits(CTransactionRef tx) = 0;
+
+    //! Estimate smart fee.
+    virtual CFeeRate estimateSmartFee(int num_blocks, bool conservative, FeeCalculation* calc = nullptr) = 0;
+
+    //! Fee estimator max target.
+    virtual unsigned int estimateMaxBlocks() = 0;
+
+    //! Pool min fee.
+    virtual CFeeRate mempoolMinFee() = 0;
 };
 
 //! Interface to let node manage chain clients (wallets, or maybe tools for