libsysprof-analyze: add bitset index

This is meant to be a simple index helper where we already have a bitset
created for a low-cardinality index. We can reuse the read-only bitset
and filter on the document itself.

This index will keep a reference on the document so it's lifetime persists.

src/libsysprof-analyze/sysprof-document-bitset-index-private.h

@@ -0,0 +1,35 @@
+/* sysprof-document-bitset-index.h
+ *
+ * Copyright 2023 Christian Hergert <chergert@redhat.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+#include <gtk/gtk.h>
+
+G_BEGIN_DECLS
+
+#define SYSPROF_TYPE_DOCUMENT_BITSET_INDEX (sysprof_document_bitset_index_get_type())
+
+G_DECLARE_FINAL_TYPE (SysprofDocumentBitsetIndex, sysprof_document_bitset_index, SYSPROF, DOCUMENT_BITSET_INDEX, GObject)
+
+GListModel *_sysprof_document_bitset_index_new (GListModel *model,
+                                                GtkBitset  *bitset);
+
+G_END_DECLS