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_jcsv_contains.sql

@@ -0,0 +1,52 @@
+
+-- =============================================
+-- Author:		<Author,,Name>
+-- Create date: <Create Date, ,>
+-- Description:	<Description, ,>
+-- =============================================
+CREATE FUNCTION [dbo].[ott_jcsv_contains]
+(
+	@groupcode varchar(10)
+	,@text varchar(4000)
+	,@fragment varchar(500)
+)
+RETURNS bit
+AS
+BEGIN
+	DECLARE @RET bit;
+	DECLARE @textinput varchar(4000) = REPLACE(ISNULL(@text, ''), ' ', '');
+
+	IF (@textinput = '' OR @textinput = '{}' OR @fragment = '')
+		BEGIN
+			SET @RET = 0;
+		END
+	ELSE
+		BEGIN
+
+			-- Will be true 
+			-- if any of the fragments exist in the list of text-items
+	
+			DECLARE @Pattern varchar(20) = '%"' + @groupcode + '":"%';
+			DECLARE @P0 int = PATINDEX(@pattern, @textinput);
+			DECLARE @P1 int = @P0 + LEN(@pattern) -2;
+			DECLARE @P2 int = CHARINDEX('"',@textinput,@p1);
+
+			IF @P0 = 0 
+				BEGIN
+					SET @RET = 0;
+
+				END
+			ELSE
+				BEGIN
+					DECLARE @text2 varchar(4000) = SUBSTRING(@textinput, @P1, @P2 - @P1);
+
+					WITH texts as (SELECT * FROM string_split(ISNULL(@text2,''), ','))
+						,fragments as (SELECT * FROM string_split(ISNULL(@fragment,''), ','))
+					SELECT @RET = CASE WHEN EXISTS (SELECT * FROM texts JOIN fragments ON texts.[value] = fragments.[value]) THEN 1 ELSE 0 END;
+				END
+
+		END
+
+	RETURN @RET;
+
+END