Complete first video in playlist

We coded along the [Installation/API Routes/Swagger Docs video](https://youtu.be/Lw-zLopB3o0?si=I6AaS1jCxhnR-QGb), did notice that this is basically a video form of the [Quick Start tutorial at FastAPI](https://fastapi.tiangolo.com), but we added comments in the `main.py` file to help be aware of how to activate the app.

We also updated the Poetry environment to get FastAPI working. Needed uvicorn as well

main.py

@@ -0,0 +1,16 @@
+from fastapi import FastAPI
+
+# use localhost:{port} in browser
+# use localhost:{port}/docs to look at the interactive, automatically created documentation
+
+app = FastAPI()
+
+
+@app.get("/")
+async def index() -> dict[str, str]:
+    return {"hello": "world"}
+
+
+@app.get("/about")
+async def about() -> str:
+    return "About MeaLeon"