Tiny Python script to send a message on a Kafka topic, because the command line tools couldn't accept as big a message as we needed.

Setup:
```
uv venv
source .venv/bin/activate
uv pip sync requirements.txt
```

Usage:
```
kafka-send.py topic path/to/message.json
```

If you want to use something other than a local Kafka server, add `-s server.host:9092`.