@Override
	public DBTraceBookmark addBookmark(Lifespan lifespan, Address address, TraceBookmarkType type,
			String category, String comment) {
		return delegateWrite(address.getAddressSpace(),
			m -> m.addBookmark(lifespan, address, type, category, comment));
	}
For non-register space:

{@code
+---12----+----52----+
| SpaceID |    Key   |
+---------+----------+
}

For register space:

{@code
+---12----+----32----+----8----+--12--+
| SpaceID |  Thread  |  Frame  |  Key |
+---------+----------+---------+------+
}
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/bookmark/DBTraceBookmarkManager.java