chore: import upstream snapshot with attribution

internal/website/docs/examples/store-postgres.md

@@ -0,0 +1,44 @@
+---
+layout: default
+---
+
+# State with Postgres Store
+
+Use the Postgres store for persistent key/value state.
+
+## In code
+
+```go
+package main
+
+import (
+    "log"
+    "go-micro.dev/v6"
+    "go-micro.dev/v6/store"
+    postgres "go-micro.dev/v6/store/postgres"
+)
+
+func main() {
+    st := postgres.NewStore()
+    svc := micro.NewService("postgres-store", micro.Store(st))
+    svc.Init()
+
+    _ = store.Write(&store.Record{Key: "foo", Value: []byte("bar")})
+    recs, _ := store.Read("foo")
+    log.Println("value:", string(recs[0].Value))
+
+    svc.Run()
+}
+```
+
+## Via environment
+
+Run your service with env vars set:
+
+```bash
+MICRO_STORE=postgres \
+MICRO_STORE_ADDRESS=postgres://user:pass@127.0.0.1:5432/postgres \
+MICRO_STORE_DATABASE=micro \
+MICRO_STORE_TABLE=micro \
+go run main.go
+```