fix(posttype): run the migration and backfill in no-args mode

The backfill hung off --ingest, --output, --correct, --importposts and
--updatepaths, because those were where EnsureTTFileHelperColumnsExist was
already being called. But the no-argument traversal is the mode that
actually gets run day to day, and it called none of them -- so the command
used most often was the one command that never repaired an untyped row.

TraverseDirectory already types the posts it inserts, from the filename it
is reading. This closes the other half: the rows already sitting untyped
now get fixed by an ordinary run, with no separate maintenance command.

Called before BeginImportSession so it uses its own connection rather than
contending with the import session's, and before the traversal so existing
rows are typed first and newly inserted ones arrive already typed.

Co-Authored-By: Claude Opus 5 <[email protected]>

URLNotesGrabberCORE/Program.cs

@@ -148,6 +148,12 @@ namespace URLNotesGrabberCORE
             if (args.Length == 0) //Traverse folder structure to add posts and thus blogs to DB
             {
                 int postsAdded = 0;
+                // This is the mode that actually gets run day to day, so the schema migration and
+                // the PostType backfill have to happen here too. They used to hang off --ingest,
+                // --output and friends only, which meant the untyped rows this traversal creates
+                // could sit unrepaired indefinitely while the one command everyone runs skipped
+                // the fix entirely. Idempotent, so paying it on every run costs nothing.
+                DataAccess.EnsureTTFileHelperColumnsExist();
                 try
                 {
                     DataAccess.EnableImportModePragmas();