atmos helmfile diff missing color without explicit --color

### Describe the Bug

Running `atmos helmfile diff` outputs a diff without coloring with no environment variable which would set any variant of `NO_COLOR`.

`atmos` itself outputs in color but the diff of `helmfile diff` is not colored.
Forcing coloring by executing `atmos helmfile diff -- --color` outputs diff in color.

### Expected Behavior

`atmos helmfile diff` outputs in color too if no variant of `NO_COLOR` is set by default without need of forcing the extra option of helmfile.

### Steps to Reproduce

1. Test that your helmfile diff outputs in color by default without atmos
2. diff through atmos
3. diff through atmos and pass the extra `--color` options to `helmfile` by appending `-- --color`

### Screenshots

_No response_

### Environment

- WSL Ubuntu 24.04
- atmos 1.220.0
- helmfile 1.4.2 (EDIT: updated to 1.5.2 w/o change)
- helm 4.2.0
- EDIT: helm diff plugin 3.15.3

### Additional Context

EDIT:
- Force uninstalling diff plugin from helm(file) doesn't change anything.
- **Applying seems to not be colored as well**

Start at the `atmos helmfile diff` command and trace how arguments are forwarded to Helmfile; reproduce the output with and without `-- --color` while checking the `NO_COLOR` environment behavior. Done means the diff is colored by default when no `NO_COLOR` variant is set, without changing the explicit color override behavior.

Written by the indexing model from the issue text.