Add MilvusConnection class

[willemarcel]

Now we have a view at /api/v1/search/ that is able to receive an audio file and execute the search in the Milvus database. That endpoint should receive a form post request with the following fields:

audio_file
limit (optional, int, max number of results)
expression (optional, str, example: subsite_name == "Wet-A")

It will get the embedding using the embed service and execute the search and return the results as JSON.

How to test:

• Create a postgres DB named bioacoustics and set the following env vars:

  export POSTGRES_USER=
  export POSTGRES_PASSWORD=
  export DJANGO_SECRET_KEY='h1g23jhg1j23h812h31282173h2g4jh213gj21'

  and also run kubectl port-forward service/milvus 9091:9091 & kubectl port-forward service/milvus 19530:19530 & to have access to the Milvus database.

[willemarcel]

@geohacker I added a commit here that also solves #6