Add support for --jq or --format=jsonpath='$.store.id'

CLI can output result in JSON format but it does not provide means to transform the output which is handy in more standardized environments like Kubernetes. For example in the readme of the CLI the suggestion to obtain the store ID is

export FGA_STORE_ID=$(fga store create --model model.fga | jq -r .store.id)

which is fine when you are in local but it imposes difficulties in container environments because e.g. the container that includes cli does not include JQ so doing this transformation would require either 2 init containers or create an image that has both cli and jq.

This is not a new issue, that is why tools like kubectl or gh include output transformations support.

For example:

• kubectl get pods -o=jsonpath="{range .items[*]}{.metadata.name}{'\t'}{.status.startTime}{'\n'}{end}"
• gh pr list --json author --jq '.[].author.login'

The issue describes the CLI's existing JSON output and the README's store-ID example; start by tracing the command path that produces JSON and reviewing the transformation approaches shown for kubectl and gh. Done means the CLI supports a defined jq or JSONPath-style transformation without requiring a separate jq container, with the README example updated accordingly.