docs(docker): Add OpenSearch backend stack to docker-compose

[jamesfisher-geo]

Some work is being done in stac-fastapi-elasticsearch-opensearch to support integration with stac-auth-proxy.

This PR adds the OpenSearch backend as an option in the docker-compose file

[alukach]

@jamesfisher-geo Thanks for putting this together! I'm out this week but will give it a try when I return.

[alukach]

Generally, looks good. I proposed some refinements in AtomicMaps#2.

[jamesfisher-geo]

Thanks @alukach! I tested your changes locally. When spinning up the os profiles after running the default docker-compose threw a build error

 => ERROR [internal] load build context                                                                                  0.0s
 => => transferring context: 57.61kB                                                                                     0.0s
 => CANCELED [stage-0 1/6] FROM docker.io/library/python:3.13-slim@sha256:4c2cf9917bd1cbacc5e9b07320025bdb7cdf2df7b0cea  0.1s
 => => resolve docker.io/library/python:3.13-slim@sha256:4c2cf9917bd1cbacc5e9b07320025bdb7cdf2df7b0ceaccb55e9dd7e309874  0.0s
 => => sha256:4c2cf9917bd1cbacc5e9b07320025bdb7cdf2df7b0ceaccb55e9dd7e30987419 9.12kB / 9.12kB                           0.0s
 => => sha256:a7cb177dc60dfa77b223192cd0d9e6ce1aac7cf9a569023d68e7c91b6371a718 1.75kB / 1.75kB                           0.0s
 => => sha256:38e57556b63539e63344b97f802e7cbd85b70e2087ee703e360fcdfe337cbbb3 5.43kB / 5.43kB                           0.0s
------
 > [internal] load build context:
------
failed to solve: error from sender: open /home/james/code/stac-auth-proxy/.pgdata: permission denied

I added .pgdata to a .dockerignore file, tested both again and it worked fine. Might be worth you trying both again locally before we merge this.

[alukach]

I added .pgdata to a .dockerignore file, tested both again and it worked fine.

@jamesfisher-geo I didn't experience that issue. Will that change interfere with it being used as a volume?

stac-auth-proxy/docker-compose.yaml

Lines 66 to 67 in 3d207e2

	volumes:
	- ./.pgdata:/var/lib/postgresql/data

I also see that we aren't using a volume for OpenSearch. Perhaps it's not that important to retain .pgdata, I think the primary value is to persist data even if we tear down the docker images...

[alukach]

Thanks again for adding this! Really helpful.

[jamesfisher-geo]

I added .pgdata to a .dockerignore file, tested both again and it worked fine.

@jamesfisher-geo I didn't experience that issue. Will that change interfere with it being used as a volume?

stac-auth-proxy/docker-compose.yaml

Lines 66 to 67 in 3d207e2

	volumes:
	- ./.pgdata:/var/lib/postgresql/data

I also see that we aren't using a volume for OpenSearch. Perhaps it's not that important to retain .pgdata, I think the primary value is to persist data even if we tear down the docker images...

Good point. My goal was to keep this as light as possible. Adding an opensearch volume is strait forward. We can simply copy the setup from SFEOS