Fix FinOps CI failures: sql_variant CONCAT and test table count

- CONVERT SERVERPROPERTY results to nvarchar(128) in CONCAT call to avoid
  implicit sql_variant conversion error (Msg 257)
- Update SchemaStatements_MatchTableCount assertion from 24 to 26 for the
  two new FinOps tables (database_size_stats, server_properties)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: erikdarlingdata

Lite.Tests/DuckDbSchemaTests.cs

@@ -136,8 +136,8 @@ public void SchemaStatements_MatchTableCount()
         foreach (var _ in Schema.GetAllTableStatements())
             tableCount++;
 
-        /* 24 tables from Schema (schema_version is created separately by DuckDbInitializer) */
-        Assert.Equal(24, tableCount);
+        /* 26 tables from Schema (schema_version is created separately by DuckDbInitializer) */
+        Assert.Equal(26, tableCount);
     }
 
     [Fact]

install/53_collect_server_properties.sql

@@ -212,9 +212,9 @@ BEGIN
                     N'SHA2_256',
                     CONCAT
                     (
-                        SERVERPROPERTY(N'Edition'), N'|',
-                        SERVERPROPERTY(N'ProductVersion'), N'|',
-                        SERVERPROPERTY(N'ProductLevel'), N'|',
+                        CONVERT(nvarchar(128), SERVERPROPERTY(N'Edition')), N'|',
+                        CONVERT(nvarchar(128), SERVERPROPERTY(N'ProductVersion')), N'|',
+                        CONVERT(nvarchar(128), SERVERPROPERTY(N'ProductLevel')), N'|',
                         @engine_edition, N'|',
                         (SELECT osi.cpu_count FROM sys.dm_os_sys_info AS osi), N'|',
                         (SELECT osi.physical_memory_kb FROM sys.dm_os_sys_info AS osi), N'|',