Fixing graphql server definition and initial README save

demo/server/README.md

@@ -4,9 +4,25 @@ This directory contains an example server (using Express) that displays how the
 
 ## Model Extension
 
-```sh
-npm install @ceramic-solutions/points
-```
+If you take a look into the [sandboxAggregation](./composites/sandboxAggregation.graphql) file, you'll notice that we've extended the `PointsAggregationInterface` interface to implement a new type - `SandboxPointAggregation`. 
+
+This new type extends the original interface to include a "context" field in its SET accountRelation, meaning that instead of 1 model instance per recipient per model, there can be 1 model instance per recipient given a certain context.
+
+The use case for this type is rewarding points within a developer sandbox. Imagine that we might want to reward participants across three categories of developer sandbox actions:
+
+1. Simple read query - yields 1 point per action (context: "read")
+2. Simple mutation - yields 5 points per action (context: "write")
+3. Complex mutation - yields 10 points per action (context: "complexWrite")
+
+In this case, we can make use of our new type to keep track of the aggregations at the context level, while still making use of the default `SimplePointsAggregation` that the library implements: [library composites](../../composites/points/schemas/1-init.graphql).
+
+## Process
+
+In order to use an extended type (like this server example uses), the following must have happened prior to running the server:
+
+1. A ComposeDB node would have been stood up with the [default library composite](../../composites/points/composite.json) deployed onto the node
+2. Next, the developer would deploy the [SandboxPointAggregation](./composites/sandboxAggregation.graphql) type (which imports one of the default library interfaces already deployed above in step 1)
+3. An .env file would have been generated at the root of this directory using the same format as [.env.example](./.env.example), using your endpoint in place of `CERAMIC_URL`, the corresponding StreamID for your `SandboxPointAggregation` model you just deployed in place of `AGGREGATION_ID`, and a private key
 
 ## License
 

demo/server/composites/sandboxAggregation.graphql

@@ -1,10 +1,10 @@
 # (for reference only)
 
-interface PointsAggregation @loadModel(id: "kjzl6hvfrbw6cb6393dpd8blke5w8r7pvbl4449mxetuibcav3oab8fnxmys6d6") {
+interface PointsAggregationInterface @loadModel(id: "kjzl6hvfrbw6cb6393dpd8blke5w8r7pvbl4449mxetuibcav3oab8fnxmys6d6") {
   id: ID!
 }
 
-type SandboxPointsAggregation implements PointsAggregation
+type SandboxPointAggregation implements PointsAggregationInterface
   @createModel(
     description: "Aggregation of multiple Ceramic Sandbox read points to an account"
     accountRelation: SET