Add Fuchs_Database SSDT project (schema source of truth)

Adds the SQL Server Data Tools project for the fuchs_fds database — tables,
table types, functions and stored procedures that the backend calls (e.g.
fds__getInvoice, fds__merge_bankingtransactions, fds__tt__bankingtransactions,
fds__admin_getReportCatalog, fis_* auth). Build/model caches (bin, obj,
*.dbmdl, *.jfm, *.user) are git-ignored.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Fuchs_Database/dbo/Functions/ott_20_randomStrings.sql

@@ -0,0 +1,27 @@
+
+-- =============================================
+-- Author:		<Author,,Name>
+-- Create date: <Create Date,,>
+-- Description:	<Description,,>
+-- =============================================
+CREATE FUNCTION [dbo].[ott_20_randomStrings]
+(
+	@digits tinyint
+)
+RETURNS @RET TABLE 
+(
+	[s] varchar(5)
+)
+AS
+BEGIN
+	
+	DECLARE @new_sessionid varchar(36), @trys int, @chars varchar(100), @UPPER int, @LOWER int;
+	SELECT @chars = '012KLMN34STUVWEFGHIJXYZ567OPQR89ABCD';
+	SELECT @UPPER = LEN(@chars), @LOWER = 1;
+		
+	INSERT INTO @RET	
+	SELECT * FROM (SELECT TOP(20) SUBSTRING(SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1) + SUBSTRING(@chars, [dbo].[ott_random_int](@UPPER,@LOWER), 1), 1, @digits) as id FROM (VALUES(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12),(13),(14),(15),(16),(17),(18),(19),(20)) vl(id))z WHERE LEN(id) = @digits;
+
+	
+	RETURN 
+END