Show database statistics when first loading UI

[prrao87]

Related to kuzudb/kuzu#5025

Use case

When a user opens their graph visualization, it's useful to immediately display the counts of all nodes/rels so that they know roughly how large a graph they're looking at.

This is common in other graph visualization tools (example below). The goal of this feature is to have a sidebar that shows these statistics so that the user immediately knows what size graph they're looking at.

G.V()

The following example shows the number of nodes and rels neatly grouped by label/table name. Once kuzudb/kuzu#5025 is merged, we will have a convenience function that allows us to retrieve this in one command rather than running multiple commands and collecting the information.

Neo4j browser

In the below example, it's immediately obvious that the graph has 43k nodes and no relationships (no need to waste time running two Cypher queries to figure that out).