feat: add 17 new cross-exchange pairs (BG↔HL)

Added: ALGO, PYTH, SAND, ADA, HBAR, IOTA, MINA, FET, WLD,
       SUI, APT, NEAR, FIL, DYDX, JUP, TIA, MOVE

Removed: pixel and VET (fake 195% spreads on testnet)

Also updated GetHLSize() to handle szDecimals for all new coins.

scanner.go

@@ -24,6 +24,24 @@ var TrackedCoins = []TrackedCoin{
 	{Name: "OP", BN: "OPUSDT", BG: "OPUSDT", HL: "OP"},
 	{Name: "WIF", BN: "WIFUSDT", BG: "WIFUSDT", HL: "WIF"},
 	{Name: "ARB", BN: "ARBUSDT", BG: "ARBUSDT", HL: "ARB"},
+	// New pairs — common on BG↔HL
+	{Name: "ALGO", BG: "ALGOUSDT", HL: "ALGO"},
+	{Name: "PYTH", BG: "PYTHUSDT", HL: "PYTH"},
+	{Name: "SAND", BG: "SANDUSDT", HL: "SAND"},
+	{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"},
+	{Name: "APT", BG: "APTUSDT", HL: "APT"},
+	{Name: "NEAR", BG: "NEARUSDT", HL: "NEAR"},
+	{Name: "FIL", BG: "FILUSDT", HL: "FIL"},
+	{Name: "DYDX", BG: "DYDXUSDT", HL: "DYDX"},
+	{Name: "JUP", BG: "JUPUSDT", HL: "JUP"},
+	{Name: "TIA", BG: "TIAUSDT", HL: "TIA"},
+	{Name: "MOVE", BG: "MOVEUSDT", HL: "MOVE"},
 }
 
 // netProfit calculates net profit % after fees for a complete round trip (entry + exit).