docs(helm): schematic diagram in mermaid format (#1358)

* docs(helm): schematic diagram in mermaid format
* Clarifies that dependencies can be external or internal to cluster
* Explicitly show namespace containing secrets

utils/helm/speckle-server/schematic.md

@@ -0,0 +1,62 @@
+# Schematic Diagram
+
+```mermaid
+graph LR;
+ client([client])-->|Ingress-managed <br> load balancer|ingress[Ingress];
+ helmrepo["Speckle Helm Chart <br> Repository"]
+ click helmrepo "https://specklesystems.github.io/helm/" _blank
+ imageregistry["Speckle OCI <br> Image Registry <br> (DockerHub)"]
+ click imageregistry "https://hub.docker.com/r/speckle/speckle-server" _blank
+ helmrepo-.->helm;
+
+ subgraph helm[Speckle Helm Chart]
+ ingress;
+ ingress-->|routing rule|svcfrontend[Frontend <br> Service];
+ ingress-->|routing rule|backend[Backend <br> Service];
+ svcfrontend;
+ backend;
+ preview[Preview <br> Service];
+ fileimport[File Import <br> Service];
+ webhook[Webhook <br> Service];
+ databasemonitor[Database Monitoring <br> Service];
+ end
+
+ subgraph namespace[Speckle Namespace]
+ helm;
+ secrets;
+ end
+
+ subgraph cluster[Kubernetes Cluster]
+ nginx["Nginx Ingress Controller (Optional)"];
+ certmanager["Certificate Manager (Optional)"];
+ monitoring["Grafana-compatible <br> metrics ingestor (Optional)"];
+ logging["Log ingestor (Optional)"];
+ namespace;
+ end
+
+ preview-->postgres;
+ fileimport-->postgres;
+ webhook-->postgres;
+ databasemonitor-->postgres;
+ backend-->postgres;
+ backend-->redis;
+ backend-->blobstore;
+ backend-->emailserver;
+ backend-->authprovider;
+
+ subgraph externalDependencies["Dependencies <br> (May be external or internal to cluster.)"]
+ postgres[Postgres];
+ redis[Redis];
+ blobstore[s3-compatible <br> blob storage];
+ emailserver["Transactional email <br> server (optional)"];
+ authprovider["Authentication provider <br> (optional)"];
+ end
+ classDef plain fill:#ddd,stroke:#fff,stroke-width:4px,color:#000;
+ classDef k8s fill:#326ce5,stroke:#fff,stroke-width:4px,color:#fff;
+ classDef cluster fill:#aaa,stroke:#bbb,stroke-width:2px,color:#000;
+ classDef helm fill:#fff,stroke:#bbb,stroke-width:2px,color:#326ce5;
+ class ingress,test,svcfrontend,backend,preview,fileimport,webhook,databasemonitor,nginx,certmanager,monitoring,logging,secrets k8s;
+ class client plain;
+ class cluster,namespace,externalDependencies cluster;
+ class helm helm;
+```