refactor: migrate system metadata to kysely (#15231)

server/src/queries/system.metadata.repository.sql

@@ -0,0 +1,24 @@
+-- NOTE: This file is auto generated by ./sql-generator
+
+-- SystemMetadataRepository.get
+select
+  "value"
+from
+  "system_metadata"
+where
+  "key" = $1
+
+-- SystemMetadataRepository.set
+insert into
+  "system_metadata" ("key", "value")
+values
+  ($1, $2)
+on conflict ("key") do
+update
+set
+  "value" = $3
+
+-- SystemMetadataRepository.delete
+delete from "system_metadata"
+where
+  "key" = $1