fix: set FORCE_COLOR=1 by default

[janishorsts]

No description provided.

[github-actions]

➖ Are we earthbuild yet?

No change in "earthly" occurrences

📈 Overall Progress

Branch	Total Count
main	7
This PR	7
Difference	+0

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Keep up the great work migrating from Earthly to Earthbuild! 🚀

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[gemini-code-assist]

Code Review

This pull request moves the export of the FORCE_COLOR environment variable to the beginning of the run function and updates it to respect existing environment values, defaulting to '1' if not set. I have no feedback to provide.