wallet: clarify difference between wallet.is_mine and adb.is_mine

related https://github.com/spesmilo/electrum/pull/8699

electrum/address_synchronizer.py

@@ -110,8 +110,14 @@ class AddressSynchronizer(Logger, EventListener):
         self.remove_local_transactions_we_dont_have()
 
     def is_mine(self, address: Optional[str]) -> bool:
-        """Returns whether an address is in our set
-        Note: This class has a larget set of addresses than the wallet
+        """Returns whether an address is in our set.
+
+        Differences between adb.is_mine and wallet.is_mine:
+        - adb.is_mine: addrs that we are watching (e.g. via Synchronizer)
+            - lnwatcher adds its own lightning-related addresses that are not part of the wallet
+        - wallet.is_mine: addrs that are part of the wallet balance or the wallet might sign for
+            - an offline wallet might learn from a PSBT about addrs beyond its gap limit
+        Neither set is guaranteed to be a subset of the other.
         """
         if not address: return False
         return self.db.is_addr_in_history(address)

electrum/wallet.py

@@ -3089,7 +3089,7 @@ class Abstract_Wallet(ABC, Logger, EventListener):
         for txin_idx, txin in enumerate(tx.inputs()):
             if txin.sighash and txin.sighash != Sighash.ALL:  # non-standard
                 addr = self.adb.get_txin_address(txin)
-                if self.adb.is_mine(addr):
+                if self.is_mine(addr):
                     sh_out = txin.sighash & (Sighash.ANYONECANPAY ^ 0xff)
                     sh_in = txin.sighash & Sighash.ANYONECANPAY
                     confirm |= hintmap[sh_out][0] | hintmap[sh_in][0]