docs: tofu/terraform group docstrings still describe the containerized environment removed in v3.0.0

[exequielrafaela]

Describe the Bug

The tofu and terraform Click group docstrings in leverage/modules/tf.py still describe the CLI as running commands in a container. The Docker dependency was removed in v3.0.0 (#316), so this text is stale.

Because these are Click group docstrings, they are rendered directly in leverage tofu --help and leverage terraform --help — this is user-facing help output, not just an internal comment.

Current Behavior

leverage/modules/tf.py, tofu group:

Run OpenTofu commands in a custom containerized environment that provides extra functionality when interacting with your cloud provider such as handling multi factor authentication for you.
All tofu subcommands that receive extra args will pass the given strings as is to their corresponding OpenTofu counterparts in the container.

The terraform group immediately below it repeats both phrases verbatim, substituting "terraform" for "tofu".

Two stale references per docstring, four in total:

Location	Stale phrase
tofu group docstring	custom containerized environment
tofu group docstring	counterparts in the container
terraform group docstring	custom containerized environment
terraform group docstring	counterparts in the container

Expected Behavior

Help text should describe the current Dockerless execution model. The rest of each docstring is still accurate — the CLI does provide extra functionality around cloud provider interaction and MFA handling — so this is a narrow wording fix, not a rewrite.

Suggested replacement for the container references:

• custom containerized environment → managed environment
• counterparts in the container → counterparts

Use Case

--help is the first place a new user looks, and onboarding docs point at it. Telling them the CLI runs in a container after the container was deliberately removed sends people looking for a Docker daemon that is no longer required, and undercuts confidence in the rest of the help output.

Additional Context

• Docker dependency removed in v3.0.0 (PR Feat | Remove docker dependency #316).
• Affects only the two group docstrings. The 12 subcommands attached to both groups (init, plan, apply, output, destroy, version, format, force-unlock, validate, validate-layout, import, refresh-credentials) have accurate one-line docstrings and need no change.
• Worth grepping the wider tree for container / docker in other user-facing strings and in the docs repo, in case the same wording survived elsewhere.