fix(#2123): Move output to stderr

[jzorn]

Description

This change moves informational command outputs from console.log (prints on stdout) to console.warn/console.error (prints on stderr) to enable stdout processing in pipelines.

This was merged already but got reverted by @helloanoop for a second review, see the comments in #2125 Was already approved by andreassiegel.

Fixes #2123 See #2125

Contribution Checklist:

• [x] The pull request only addresses one issue or adds one feature.
• [x] The pull request does not introduce any breaking changes
• [x] I have added screenshots or gifs to help explain the change if applicable.
• [x] I have read the contribution guidelines.
• [x] Create an issue and link to the pull request.

Note: Keeping the PR small and focused helps make it easier to review and merge. If you have multiple changes you want to make, please consider submitting them as separate pull requests.

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