Remove leading comma from first column?

Question

I am writing the following dynamic SQL, and getting an error in the PIVOT section of the View creation.

Incorrect syntax near ','

FOR [Accounts] IN (
                ' + @pivotColumns + '

I know why, its because there shouldn't be a comma that precedes the FIRST @pivotColumn (see image below for example). However, the column is a result of dynamic SQL, how do I go about resolving this? And I cant use trailing comma instead because then I will have a similar problem with the last column.

Basically, I need a way to make

SELECT @pivotColumns =....

not append a leading comma to the FIRST column/Account selected.

The comma is added at the end at this part of @pivotColumns:

',', quotename

Full Query:

DECLARE @sqlCommand NVARCHAR(MAX) = '',
        @columnList NVARCHAR(MAX) = '',
        @pivotColumns NVARCHAR(MAX) = '';

SELECT @columnList = STUFF(
   (SELECT DISTINCT concat(CHAR(9), ',', 'COALESCE(', quotename(AccTbl.Account), ', 0)', quotename(AccTbl.Account), CHAR(10))
    FROM [Accounts] AccTbl
    --WHERE AccTbl.Active = 'YES'
    WHERE AccTbl.Account NOT IN ('WS')
    FOR XML Path(''), TYPE).value('(./text())[1]', 'NVARCHAR(MAX)'), 1, 1, '');

SELECT @pivotColumns = STUFF(
   (SELECT DISTINCT concat(CHAR(9), ',', quotename(AccTbl.Account), CHAR(10))
    FROM [Accounts] AccTbl
    WHERE AccTbl.Account NOT IN ('WS')
    FOR XML Path(''), TYPE).value('(./text())[1]', 'NVARCHAR(MAX)'), 1, 1, '');

/*
EXEC the sqlCommand as separate batches to prevent this error: 'CREATE VIEW' must be the first statement in a query batch.
https://stackoverflow.com/a/39135516/8397835
*/

SET @sqlCommand = '
    USE [ABC_DB]
    --GO
    DROP VIEW IF EXISTS [dbo].[Piv];
    --GO
    SET ANSI_NULLS ON
    --GO
    SET QUOTED_IDENTIFIER ON
    --GO
';

Execute sp_executesql @sqlCommand;

SET @sqlCommand = '
    CREATE VIEW [dbo].[Piv]
    AS
    (SELECT
      [Style Code],
      ' + @columnList + '
    FROM [History] 
        PIVOT (SUM([Value]) FOR [Accounts] IN (
            ' + @pivotColumns + '
            )
        ) 
    AS Piv);
';

PRINT @sqlCommand;
Execute sp_executesql @sqlCommand;

In other words, whats happening right now is something like this: