feat(api): Created openapi based pubic API contracts

- made DTOs
- created an api-client

packages/api-client/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "rootDir": "src",
+    "outDir": "dist"
+  },
+  "include": ["src"],
+  "references": [{ "path": "../api-contracts" }]
+}