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_b10.sql

@@ -0,0 +1,43 @@
+
+-- =============================================
+-- Author:		<Author,,Name>
+-- Create date: <Create Date, ,>
+-- Description:	<Description, ,>
+-- =============================================
+CREATE FUNCTION [dbo].[ott_b10]
+(
+	@string varchar(10)
+)
+RETURNS int
+AS
+BEGIN
+	DECLARE @RET int;
+
+
+	DECLARE @str VARCHAR(10) = REVERSE(LOWER(@string));
+	WITH Split(stpos,endpos) AS(
+			SELECT 1 AS stpos, 2 AS endpos
+			UNION ALL
+			SELECT endpos, endpos+1
+			FROM Split
+			WHERE endpos <= LEN(@str)
+	)
+	, c as (
+		SELECT 
+			'character' = SUBSTRING(@str,stpos,COALESCE(NULLIF(endpos,0),LEN(@str)+1)-stpos)
+		   ,'charindex' = stpos
+		FROM Split
+	)
+	, s as (
+		SELECT 
+			*
+			,'num' = ASCII(character) - ASCII('a') + 1
+			,'fac' = POWER(26,([charindex] -1))
+			,'val' = POWER(26,([charindex] -1)) *  (ASCII(character) - ASCII('a') + 1)
+		FROM c
+	)
+	select @RET = SUM([val]) FROM s;
+	
+	RETURN @RET;
+
+END