fix: use BIP-352 activation height

* this allows the indexer to skip blocks that do not support
silent payments
* https://www.bitaps.com/842579
* bitcoin/bips#1458

Author: notTanveer

src/common/vars.go

@@ -38,10 +38,7 @@ const (
 
 // control vars
 var (
-	SyncStartHeight uint32 = 833_000 // random block where BIP352 was not active yet. todo change to actual number
-	// MinHeightToProcess No block below this number will be processed
-	// todo is this actually needed
-	//MinHeightToProcess uint32 = 833_000
+	SyncStartHeight uint32 = 842_579 // May 8, 2024, when BIP-352 was merged
 
 	Chain = Unknown