feat: Implement mfr truncation fix and enhance invoice handling

- Added a new SQL script to address the "String or binary data would be truncated" error in mfr sync by widening the Note fields in service objects and companies to NVARCHAR(MAX).
- Updated the table types and associated stored procedures to accommodate the changes, ensuring compatibility with existing data.
- Queued a re-sync for previously rejected rows due to truncation issues.
- Created application logins for fuchs_fds and fuchs_web with placeholder passwords for initial setup.
- Introduced functions for invoice backdating and invoice date retrieval to streamline invoice processing.
- Developed a password generation function with customizable parameters for length and character types.
- Added a random number generation function to support password creation.

Fuchs_Database/dbo/Functions/fds__fn_IntermediateIsAllocatedToOther.sql

@@ -12,9 +12,13 @@ CREATE FUNCTION [dbo].[fds__fn_IntermediateIsAllocatedToOther]
 RETURNS bit
 AS
 BEGIN
-	DECLARE @IsA bit = CASE WHEN EXISTS (SELECT * FROM [dbo].[fds__invoices] as intermediates JOIN [dbo].[fds__invoice_details] as id on intermediates.[Id] = id.[InvId] and id.[AllocatedTo_InvId] is not null
+	-- An allocation only counts while the crediting invoice is alive: once that invoice is cancelled
+	-- (storno) its credit line is void and the Abschlagsrechnung must be offered again (ADR 0034).
+	DECLARE @IsA bit = CASE WHEN EXISTS (SELECT 1 FROM [dbo].[fds__invoices] as intermediates JOIN [dbo].[fds__invoice_details] as id on intermediates.[Id] = id.[InvId] and id.[AllocatedTo_InvId] is not null
 														JOIN [dbo].[fds__invoices] as non_intermediates ON id.[AllocatedTo_InvId] = non_intermediates.[Id] and id.[AllocatedTo_InvId] is not null
-													WHERE intermediates.[Id] = @Intermediate_InvID and (@Target_InvID is null or non_intermediates.[Id] <> @Target_InvID))
+													WHERE intermediates.[Id] = @Intermediate_InvID
+														and ISNULL(non_intermediates.[IsCanceled], 0) = 0
+														and (@Target_InvID is null or non_intermediates.[Id] <> @Target_InvID))
 									THEN 1 ELSE 0 END;
 
 	RETURN @isA;