add flag to disable https OIDC state cookie

[RA341]

Describe the bug
remove the https restriction on OIDC state cookie to allow for non http dockman instances to use OIDC

Original issue: #172

func to fix: https://github.com/RA341/dockman/blob/811de7085769df3c66a904b6975217c28474b282/core/internal/auth/handler_http.go#L26C1-L42C1

[github-actions]

✅ This issue has been implemented in the canary build!

You can test it by running:

docker run --rm -p 8866:8866 -e DOCKMAN_LOG_AUTH_WARNING=false -v /var/run/docker.sock:/var/run/docker.sock ghcr.io/ra341/dockman:canary

Please share any feedback or issues you encounter.

⚠️ Note: Canary builds are unstable and may contain breaking changes.