perf: set GOGC=200 to reduce GC frequency

Reduces GC CPU overhead (~17% of total) by allowing the heap to grow
larger before triggering collection. Benchmarked at +3.2% avg TPS.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: pdrobnjak

app/app.go

@@ -440,6 +440,8 @@ func New(
 	appOptions []AppOption,
 	baseAppOptions ...func(*baseapp.BaseApp),
 ) *App {
+	debug.SetGCPercent(200)
+
 	appCodec := encodingConfig.Marshaler
 	cdc := encodingConfig.Amino
 	interfaceRegistry := encodingConfig.InterfaceRegistry