feat: add prismic env commands and active environment state

[angeloashmore]

Resolves:

Note

Base of a 3-PR stack that splits the environments work for reviewability:

• feat: add prismic env commands and active environment state #218 (this PR) — active-environment state + prismic env commands
• feat: resolve commands against the active environment #219 — resolve existing commands against the active environment (stacked on this)
• feat: inject the active environment via prismic/env/register #220 — prismic/env/register preload for running apps (stacked on feat: resolve commands against the active environment #219; its pr-220 prerelease carries the full flow for testing)

Description

Adds a prismic env command group to choose which Prismic environment a project targets, and the state model behind it.

A Prismic environment is a separate repository domain, so the active environment is just the repo domain the CLI targets by default. The CLI stores it in its config dir, keyed by project path. It does not touch .env files.

Commands

prismic env list          # environments you can access, active one marked
prismic env set <domain>  # target an environment
prismic env unset         # reset to production
prismic env active        # print the active environment

State

A flat project path → environment domain map:

// ~/.config/prismic/environments.json
{
  "file:///path/to/project/": "my-repo-staging"
}

This PR only introduces the state and the management commands. Wiring the active environment into push/pull/status/etc. is #219, and the app-side preload is #220. resolveEnvironment is kept here and removed in #219.

Checklist

• A comprehensive Linear ticket, providing sufficient context and details to facilitate the review of the PR, is linked to the PR.
• If my changes require tests, I added them.
• If my changes affect backward compatibility, it has been discussed.
• If my changes require an update to the CONTRIBUTING.md guide, I updated it.

Preview

How to QA ¹

prismic env list          # available environments
prismic env set my-repo-staging
prismic env active        # my-repo-staging
prismic env unset
prismic env active        # prints the production domain

Footnotes

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