Capture mesh-catalog at feat/r4g (2246ccc4) with the templates its manifests name and its predefined.json, and lay the copy out as a repository's root

The catalogue's manifests moved their content into template files and fall back to predefined keys, so a copy of
module.json alone no longer passes the catalogue's own check; the bus's Dockerfile is gone from the catalogue.

testdata/beside/mesh-catalog/modules/mssql/files/backup.sql

@@ -0,0 +1,14 @@
+SET NOCOUNT ON;
+DECLARE @n sysname, @s nvarchar(max);
+DECLARE c CURSOR LOCAL FAST_FORWARD FOR
+  SELECT name FROM sys.databases WHERE database_id > 4 AND state = 0 AND source_database_id IS NULL;
+OPEN c;
+FETCH NEXT FROM c INTO @n;
+WHILE @@FETCH_STATUS = 0
+BEGIN
+  SET @s = N'BACKUP DATABASE ' + QUOTENAME(@n) + N' TO DISK = N''/var/opt/mssql/backup/' + REPLACE(@n, N'''', N'''''') + N'.bak'' WITH INIT, COPY_ONLY, CHECKSUM';
+  EXEC (@s);
+  FETCH NEXT FROM c INTO @n;
+END
+CLOSE c;
+DEALLOCATE c;