Improve cypher aggregation docs

* how labels and properties are picked
* parameters inside the node and relationshipConfig
* fix the optional parameters intro

Author: FlorentinD

doc/modules/ROOT/pages/management-ops/projections/graph-project-cypher-aggregation.adoc

@@ -3,35 +3,43 @@
 :description: This section details projecting GDS graphs using `Cypher` aggregations.
 
 
+Using Cypher aggregations is a more flexible and expressive approach with diminished focus on performance compared to the xref:management-ops/projections/graph-project.adoc[native projections].
+Cypher aggregations are primarily recommended for the development phase (see xref:common-usage/index.adoc[Common usage]).
 
-A projected graph can be stored in the catalog under a user-defined name.
-Using that name, the graph can be referred to by any algorithm in the library.
-This allows multiple algorithms to use the same graph without having to project it on each algorithm run.
 
-Using Cypher aggregations is a more flexible and expressive approach with diminished focus on performance compared to the xref:management-ops/projections/graph-project.adoc[native projections].
-Cypher projections are primarily recommended for the development phase (see xref:common-usage/index.adoc[Common usage]).
+== Considerations
 
-[NOTE]
---
-There is also a way to generate a random graph, see xref:management-ops/projections/graph-generation.adoc[Graph Generation] documentation for more details.
---
+=== Lifecycle
 
 [NOTE]
 --
-The projected graph will reside in the catalog until:
+The projected graphs will reside in the catalog until either:
 
 - the graph is dropped using xref:graph-drop.adoc[gds.graph.drop]
 - the Neo4j database from which the graph was projected is stopped or dropped
 - the Neo4j database management system is stopped.
 --
 
 
+=== Node property support
+
+Cypher aggregations can only project a limited set of node property types from a Cypher query.
+The xref:management-ops/node-properties.adoc#node-properties-supported[Node Properties page] details which node property types are supported.
+Other types of node properties have to be transformed or encoded into one of the supported types in order to be projected using a Cypher aggregation.
+
+=== Selection of node properties and labels
+
+If a node occurs multiple times, the node properties and labels of the first occurrence will be used for the projection.
+This is important when a node can be a source node as well as a target node.
+
+
 [[graph-project-cypher-aggregation-syntax]]
 == Syntax
 
 A Cypher aggregation is used in a query as an aggregation over the relationships that are being projected.
 It takes three mandatory arguments: `graphName`, `sourceNode` and `targetNode`.
-In addition, the optional `sourceNodeProperties`, `targetNodeProperties`, and `relationshipProperties` parameters allows us to project properties.
+In addition, the optional `nodesConfig`, `relationshipConfig` parameters can be used to project properties and label or types.
+The optional `configuration` parameter can be used for general configuration of the projection such as `readConcurrency`.
 
 [.graph-project-cypher-aggregation-syntax]
 --
@@ -53,15 +61,35 @@ RETURN gds.alpha.graph.project(
 ----
 
 .Parameters
-[opts="header",cols="1,1,8"]
+[opts="header",cols="2,1,7"]
 |===
 | Name               | Optional | Description
 | graphName          | no       | The name under which the graph is stored in the catalog.
 | sourceNode         | no       | The source node of the relationship. Must not be null.
 | targetNode         | yes      | The target node of the relationship. The targetNode can be null (for example due to an `OPTIONAL MATCH`), in which case the source node is projected as an unconnected node.
-| nodesConfig        | yes      | Properties and Labels configuration for the source and target nodes.
-| relationshipConfig | yes      | Properties and Type configuration for the relationship.
-| configuration      | yes      | Additional parameters to configure the cypher aggregation projection.
+| <<graph-project-cypher-aggregation-syntax-nodesConfig, nodesConfig>>        | yes      | Properties and Labels configuration for the source and target nodes.
+| <<graph-project-cypher-aggregation-syntax-relationshipConfig, relationshipConfig>> | yes      | Properties and Type configuration for the relationship.
+| <<graph-project-cypher-aggregation-syntax-configuration, configuration>>      | yes      | Additional parameters to configure the cypher aggregation projection.
+|===
+
+[[graph-project-cypher-aggregation-syntax-nodesConfig]]
+.Nodes configuration
+[opts="header",cols="1,1,1,4"]
+|===
+| Name                 | Type                     | Default | Description
+| sourceNodeProperties | Map                      | {}      | The properties of the source node.
+| targetNodeProperties | Map                      | {}      | The properties of the target node.
+| sourceNodeLabels     | List of String or String | []      | The label(s) of the source node.
+| targetNodeLabels     | List of String or String | []      | The label(s) of the source node.
+|===
+
+[[graph-project-cypher-aggregation-syntax-relationshipConfig]]
+.Relationship configuration
+[opts="header",cols="1,1,1,4"]
+|===
+| Name                 | Type          | Default | Description
+| properties           | Map           | {}      | The properties of the source node.
+| relationshipType     | String        | '*'     | The type of the relationship.
 |===
 
 [[graph-project-cypher-aggregation-syntax-configuration]]