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/fds__admin_reminderSettings.sql

@@ -0,0 +1,18 @@
+-- =============================================
+-- Author:		<Author,,Name>
+-- Create date: <Create Date,,>
+-- Description:	<Description,,>
+-- =============================================
+CREATE FUNCTION [dbo].[fds__admin_reminderSettings]
+(	
+
+)
+RETURNS TABLE 
+AS
+RETURN 
+(
+	WITH rs as ( SELECT * FROM [dbo].[fds__admin_settings] WHERE [type] = 'reminder' )
+	SELECT [stage1] = (SELECT TOP(1) [value] FROM rs WHERE [key] = 1)
+		, [stage2] = (SELECT TOP(1) [value] FROM rs WHERE [key] = 2)
+		, [stage3] = (SELECT TOP(1) [value] FROM rs WHERE [key] = 3)
+)