Have fts5 interpret column lists that begin with a "-" character as "match any column except" lists.

FossilOrigin-Name: e517545650631d1e8a7ee63c6646a8b183a0a894

ext/fts5/fts5_index.c

@@ -3195,6 +3195,14 @@ static void fts5IterSetOutputs_Nocolset(Fts5Iter *pIter, Fts5SegIter *pSeg){
   }
 }
 
+/*
+** xSetOutputs callback used when the Fts5Colset object has nCol==0 (match
+** against no columns at all).
+*/
+static void fts5IterSetOutputs_ZeroColset(Fts5Iter *pIter, Fts5SegIter *pSeg){
+  pIter->base.nData = 0;
+}
+
 /*
 ** xSetOutputs callback used by detail=col when there is a column filter
 ** and there are 100 or more columns. Also called as a fallback from
@@ -3300,6 +3308,10 @@ static void fts5IterSetOutputCb(int *pRc, Fts5Iter *pIter){
       pIter->xSetOutputs = fts5IterSetOutputs_Nocolset;
     }
 
+    else if( pIter->pColset->nCol==0 ){
+      pIter->xSetOutputs = fts5IterSetOutputs_ZeroColset;
+    }
+
     else if( pConfig->eDetail==FTS5_DETAIL_FULL ){
       pIter->xSetOutputs = fts5IterSetOutputs_Full;
     }