fix: add a Settings toggle for known-symbol spoof verification (closes #176)

docs/README.md

@@ -323,7 +323,14 @@ by default:
 **Known token symbol verification.** AutistMask ships a list of roughly 500
 legitimate ERC-20 tokens with their contract addresses. If a transaction or
 balance claims to involve a known symbol (like "ETH" or "USDT") but comes from
-an unrecognized contract, it is identified as a spoof and hidden.
+an unrecognized contract, it is identified as a spoof and hidden. In your
+transaction history this is the "Hide fake tokens impersonating a known symbol"
+setting, which you can switch off; doing so also stops new entries being added
+to the fraud contract blocklist below, since detecting a spoof is what fills it.
+The send token list always applies the check. Your balances apply it too, with
+one exception: a token claiming the symbol "ETH" is not filtered there, so a
+fake "ETH" token can still show up in your balance list even though it is hidden
+from your transaction history and from the send token list.
 
 **Low-holder token filtering.** Tokens with fewer than 1,000 holders are hidden
 from transaction history and the send token list, and are left out of your