Add ETH and USDC balance check before start/restart bot and autoswap

src/Managing.Application/Bots/TradingBotBase.cs

@@ -6,6 +6,7 @@ using Managing.Application.Trading.Commands;
 using Managing.Application.Trading.Handlers;
 using Managing.Common;
 using Managing.Core;
+using Managing.Core.Exceptions;
 using Managing.Domain.Accounts;
 using Managing.Domain.Bots;
 using Managing.Domain.Candles;
@@ -822,6 +823,17 @@ public class TradingBotBase : ITradingBot
 
                 return null;
             }
+            catch (InsufficientFundsException ex)
+            {
+                // Handle insufficient funds errors with user-friendly messaging
+                SetSignalStatus(signal.Identifier, SignalStatus.Expired);
+                await LogWarning(ex.UserMessage);
+                
+                // Log the technical details for debugging
+                Logger.LogError(ex, "Insufficient funds error for signal {SignalId}: {ErrorMessage}", signal.Identifier, ex.Message);
+                
+                return null;
+            }
             catch (Exception ex)
             {
                 SetSignalStatus(signal.Identifier, SignalStatus.Expired);