opt: assign table ID to hypothetical inverted index columns

This commit fixes a minor bug in index recommendations where
hypothetical inverted index columns were not assigned table IDs in the
hypothetical table's metadata. In theory this could cause internal
errors, however, there are no known reproductions of errors.

Release note: None

Author: mgartner

pkg/sql/opt/indexrec/testdata/geospatial

@@ -1792,7 +1792,7 @@ select
  │         ├── cost: 142.706667
  │         ├── key: (3)
  │         └── scan t2@inverted_idx,inverted
- │              ├── columns: rowid:3!null t2.geom1_inverted_key:6!null
+ │              ├── columns: rowid:3!null geom1_inverted_key:6!null
  │              ├── inverted constraint: /6/3
  │              │    └── spans
  │              │         ├── ["B\xfd\x10\x00\x00\x00\x00\x00\x00\x00", "B\xfd\x10\x00\x00\x00\x00\x00\x00\x00"]
@@ -1935,7 +1935,7 @@ select
  │         ├── cost: 142.706667
  │         ├── key: (3)
  │         └── scan t2@inverted_idx_visible,inverted
- │              ├── columns: rowid:3!null t2.geom1_inverted_key:8!null
+ │              ├── columns: rowid:3!null geom1_inverted_key:8!null
  │              ├── inverted constraint: /8/3
  │              │    └── spans
  │              │         ├── ["B\xfd\x10\x00\x00\x00\x00\x00\x00\x00", "B\xfd\x10\x00\x00\x00\x00\x00\x00\x00"]

pkg/sql/opt/metadata.go

@@ -1015,7 +1015,8 @@ func (md *Metadata) UpdateTableMeta(
 			// will have extra inverted columns added. Add any new inverted columns to
 			// the metadata.
 			for j, n := oldTable.ColumnCount(), newTable.ColumnCount(); j < n; j++ {
-				md.AddColumn(string(newTable.Column(j).ColName()), types.Bytes)
+				colID := md.AddColumn(string(newTable.Column(j).ColName()), types.Bytes)
+				md.ColumnMeta(colID).Table = md.tables[i].MetaID
 			}
 			if newTable.ColumnCount() > oldTable.ColumnCount() {
 				// If we added any new columns, we need to recalculate the not null