feat: resolve commands against the active environment

[angeloashmore]

Resolves:

Note

Middle of the stack: #218 → #219 (this PR) → #220. Merge #218 first — this PR targets its branch, and #220 targets this one.

Description

Migrates every repo-facing command (push, pull, sync, status, and the locale/preview/token/webhook groups) to resolve its target repository in priority order:

1. the --repo flag, if passed (--env is a deprecated alias, still supported)
2. the active environment, if set (from feat: add prismic env commands and active environment state #218)
3. the project's repository domain (the production default)

--env becomes a deprecated alias for --repo, and the now-unused resolveEnvironment helper is removed.

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 set my-repo-staging
prismic status            # now targets the environment without --env
prismic pull --repo my-other-repo   # --repo still overrides
prismic pull --env my-other-repo    # deprecated alias, still works

Footnotes

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