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/Stored Procedures/fds__setInvoiceFinal.sql

@@ -5,7 +5,8 @@
 -- =============================================
 CREATE PROCEDURE [dbo].[fds__setInvoiceFinal]
 	@Id varchar(8),
-	@authuser varchar(25)
+	@authuser varchar(25),
+	@backdate bit = 0	-- 1: date the invoice to the last working day of the previous month (ADR 0032)
 AS
 BEGIN
 	SET NOCOUNT ON;
@@ -13,10 +14,33 @@ BEGIN
 		THROW 60000, N'not authorized', 1;  
 	
 	INSERT INTO [dbo].[fds__admin_activity] ([activity] ,[authuser] ,[info])
-		VALUES ('fds__setInvoiceFinal' ,@authuser , (SELECT * FROM (VALUES(@Id, @authuser)) as z ([id],[authuser]) FOR JSON PATH, INCLUDE_NULL_VALUES, WITHOUT_ARRAY_WRAPPER));
+		VALUES ('fds__setInvoiceFinal' ,@authuser , (SELECT * FROM (VALUES(@Id, @authuser, @backdate)) as z ([id],[authuser],[backdate]) FOR JSON PATH, INCLUDE_NULL_VALUES, WITHOUT_ARRAY_WRAPPER));
 
 	DECLARE @now datetime = GETUTCDATE();
 
+	-- Finalizations are serialized: the "no later invoice" check of fds__fn_invoiceBackdate and the
+	-- numbering UPDATE below must not interleave with a concurrent finalization, or a higher invoice
+	-- number could end up with an earlier DateFinalized (ADR 0032). The app lock is transaction-owned
+	-- and released at COMMIT/ROLLBACK; every finalization (backdated or not) takes it.
+	SET XACT_ABORT ON;
+	BEGIN TRY
+	BEGIN TRANSACTION;
+	DECLARE @lock int;
+	EXEC @lock = sp_getapplock @Resource = N'fds__setInvoiceFinal', @LockMode = N'Exclusive', @LockOwner = N'Transaction', @LockTimeout = 15000;
+	IF @lock < 0
+		THROW 60002, N'invoice finalization lock not acquired', 1;
+
+	-- Invoice date: now, or (admins, fds_inv > 2) the last working day of the previous month as long as
+	-- no invoice has been finalized after it. Noon keeps the UTC-stored value on the same calendar day.
+	DECLARE @finalized datetime = @now, @backdateDay date = NULL;
+	IF ISNULL(@backdate, 0) = 1
+	BEGIN
+		SET @backdateDay = [dbo].[fds__fn_invoiceBackdate](@authuser);
+		IF @backdateDay IS NULL
+			THROW 60001, N'backdating not allowed', 1;
+		SET @finalized = DATEADD(HOUR, 12, CAST(@backdateDay AS datetime));
+	END
+
 	DECLARE @ids as TABLE([Id] varchar(10));
 
 	DECLARE @Replaces TABLE([RefInvID] varchar(10));
@@ -24,7 +48,9 @@ BEGIN
 	DECLARE @Replaces_InvId varchar(50) = CASE WHEN EXISTS(SELECT * FROM @Replaces) THEN STUFF( (SELECT ',' + [refinvid] as [Text] FROM @replaces FOR XML PATH, TYPE).value('.', 'nvarchar(max)'), 1, 1, '') ELSE NULL END;
 
 
-    UPDATE [dbo].[fds__invoices] SET [DateFinalized] = @now, [UserFinalized] = @authuser, [DateModified] = @now, [UserModified] = @authuser, [invoiceid] = [dbo].[fds__newInvoiceId](Year(@now)), [version] = (ISNULL([version],0) + 1), [Replaces_InvId] = @Replaces_InvId
+    UPDATE [dbo].[fds__invoices] SET [DateFinalized] = @finalized, [UserFinalized] = @authuser, [DateModified] = @now, [UserModified] = @authuser, [invoiceid] = [dbo].[fds__newInvoiceId](Year(@finalized)),
+		[DueDate] = CASE WHEN @backdateDay IS NULL THEN [DueDate]	-- same term arithmetic as fds__setInvoice, anchored on the backdated invoice date
+						ELSE DATEADD(DAY, ISNULL(TRY_PARSE(REPLACE(REPLACE(ISNULL([PaymentTerm], '10wd'), 'w', ''), 'd', '') AS tinyint), 10), @backdateDay) END, [version] = (ISNULL([version],0) + 1), [Replaces_InvId] = @Replaces_InvId
 	OUTPUT inserted.[id]
 		INTO @ids
 	WHERE [Id] = @Id AND @Id is not null and [isFinal] = 0 and [isSent] = 0;
@@ -32,35 +58,54 @@ BEGIN
 	SELECT iv.* FROM [dbo].[fds__invoices] as iv JOIN @ids as ids on iv.[id] = ids.Id;   --this is necessary to get calculated fields also
 
 
-	--  update references of intermediate invoices
+	--  update references of intermediate invoices (ADR 0034)
 	WITH IntInvoiceAllocs as(
-		SELECT [tgtInvId] = @Id, [reference_InvId] FROM [dbo].[fds__invoice_items] where [Type] = 'IntInvoiceAllocation' AND [InvId] = @Id
+		SELECT DISTINCT [tgtInvId] = @Id, [reference_InvId] FROM [dbo].[fds__invoice_items] where [Type] = 'IntInvoiceAllocation' AND [InvId] = @Id
+			AND ISNULL([reference_InvId], '') <> ''	-- a NULL reference used to abort this MERGE (515 on fds__invoice_details.InvId)
+			-- a Stornorechnung (copy) mirrors the cancelled invoice's credit lines but consumes no Abschlagsrechnung
+			AND EXISTS (SELECT * FROM [dbo].[fds__invoices] as me WHERE me.[Id] = @Id AND me.[InvoiceType] <> 'c')
 	), existing as (
-		SELECT intermediates.Id 
-			FROM [dbo].[fds__invoice_details] as id 
-				JOIN [dbo].[fds__invoices] as intermediates on id.[InvId] = intermediates.[id] 
+		-- intermediates already credited on ANOTHER *live* invoice: a credit on a cancelled invoice, or on the
+		-- invoice this one replaces (storno + recreate), is void and may be taken over
+		SELECT intermediates.Id
+			FROM [dbo].[fds__invoice_details] as id
+				JOIN [dbo].[fds__invoices] as intermediates on id.[InvId] = intermediates.[id]
 				JOIN IntInvoiceAllocs as iia on iia.[reference_InvId] = intermediates.[Id]
+				JOIN [dbo].[fds__invoices] as tgt on tgt.[Id] = id.[AllocatedTo_InvId]	-- (a dangling AllocatedTo_InvId counts as free)
 			WHERE ISNULL(intermediates.[iscanceled], 0) = 0 AND isnull(intermediates.[isfinal],0) = 1    -- reallocation is allowed for cancelled inv.
-				and ISNULL(id.[AllocatedTo_InvId], '6AA609E8-1') <> @id 
+				and tgt.[Id] <> @Id	-- (an unallocated one used to count as taken, so nothing was ever allocated)
+				and ISNULL(tgt.[IsCanceled], 0) = 0
+				and NOT EXISTS (SELECT * FROM @Replaces as r WHERE r.[RefInvID] = tgt.[Id])
 	)
 	MERGE [dbo].[fds__invoice_details] as TARGET
 		USING IntInvoiceAllocs as iia ON TARGET.[InvID] = iia.[reference_InvId]
-	WHEN NOT MATCHED BY TARGET 
-		AND NOT EXISTS (SELECT * FROM existing WHERE existing.[id] = iia.[reference_InvId])  THEN 
+	WHEN NOT MATCHED BY TARGET
+		AND NOT EXISTS (SELECT * FROM existing WHERE existing.[id] = iia.[reference_InvId])  THEN
 		INSERT ([InvId] ,[AllocatedTo_InvId])
 		VALUES (iia.[reference_InvId], iia.[tgtInvId])
-	WHEN NOT MATCHED BY SOURCE THEN
-		UPDATE 
-			SET [AllocatedTo_InvId] = NULL 
+	WHEN MATCHED	-- free, ours already, or held by a cancelled/replaced invoice -> (re)allocate to this one
+		AND NOT EXISTS (SELECT * FROM existing WHERE existing.[id] = iia.[reference_InvId]) THEN
+		UPDATE
+			SET [AllocatedTo_InvId] = iia.[tgtInvId]
+	WHEN NOT MATCHED BY SOURCE AND TARGET.[AllocatedTo_InvId] = @Id THEN	-- only this invoice's own stale allocations (was: every row of the table)
+		UPDATE
+			SET [AllocatedTo_InvId] = NULL
 	;
 
 	--updated replaced invoices
 	 UPDATE refinv
-		SET [DateCancelled] = @now, [UserCancelled] = @authuser, [version] = (ISNULL([version],0) + 1)
+		SET [DateCancelled] = @finalized, [UserCancelled] = @authuser, [version] = (ISNULL([version],0) + 1)
 	FROM [dbo].[fds__invoices] as refinv JOIN @Replaces as r on refinv.Id = r.[RefInvID]
 		WHERE refinv.[isFinal] = 1 and refinv.[IsCanceled] = 0;
 
 
 	--update replaced invoices   (by stornos)
 	EXECUTE [dbo].[fds__maint__updateCancelledStatus];
+
+	COMMIT TRANSACTION;
+	END TRY
+	BEGIN CATCH
+		IF @@TRANCOUNT > 0 ROLLBACK TRANSACTION;
+		THROW;	-- keeps the original number (60001 = backdating not allowed) for the caller
+	END CATCH;
 END