fix: full arb table + net profit columns in price view

- ArbTable: removed slice(0,10) cap, shows all 42 opps (21x2)
- PriceTable: added net_bg_to_hl and net_hl_to_bg columns
- Backend SSE: sends net profit for both directions per coin

scanner.go

@@ -31,7 +31,6 @@ var TrackedCoins = []TrackedCoin{
 	{Name: "ADA", BG: "ADAUSDT", HL: "ADA"},
 	{Name: "HBAR", BG: "HBARUSDT", HL: "HBAR"},
 	{Name: "IOTA", BG: "IOTAUSDT", HL: "IOTA"},
-	{Name: "MINA", BG: "MINAUSDT", HL: "MINA"},
 	{Name: "FET", BG: "FETUSDT", HL: "FET"},
 	{Name: "WLD", BG: "WLDUSDT", HL: "WLD"},
 	{Name: "SUI", BG: "SUIUSDT", HL: "SUI"},