✨ feat: Add auth flow (#146)

This adds a simple way to incorporate a centralized authentication flow.

The idea is to have the user, API and SSH (for machine authentication)
all in one place using `openauthjs` + `SST`

We also have a database now :)

> We are using InstantDB as it allows us to authenticate a use with just
the email. Plus it is super simple simple to use _of course after the
initial fumbles trying to design the db and relationships_

packages/core/src/user/index.ts

@@ -0,0 +1,37 @@
+import { z } from "zod";
+import databaseClient from "../database"
+import { fn } from "../utils";
+import { Common } from "../common";
+import { Examples } from "../examples";
+
+export module User {
+    export const Info = z
+        .object({
+            id: z.string().openapi({
+                description: Common.IdDescription,
+                example: Examples.User.id,
+            }),
+            email: z.string().nullable().openapi({
+                description: "Email address of the user.",
+                example: Examples.User.email,
+            }),
+        })
+        .openapi({
+            ref: "User",
+            description: "A Nestri console user.",
+            example: Examples.User,
+        });
+
+    export const fromEmail = fn(z.string(), async (email) => {
+        const db = databaseClient()
+        const res = await db.auth.getUser({ email })
+        return res
+    })
+
+    export const create = fn(z.string(), async (email) => {
+        const db = databaseClient()
+        const token = await db.auth.createToken(email)
+
+        return token
+    })
+}