chore: add CODEOWNERS so the code-owner review rule has effect

[AndreaSucreG]

The main ruleset sets require_code_owner_review: true, but there was no
CODEOWNERS file anywhere (root, .github/, docs/) — so that rule was silently
a no-op and the protection config overstated what it actually enforced.

This adds .github/CODEOWNERS making @AndreaSucreG the sole owner of *.
Every change to the repo therefore needs her approval.

Known consequence: GitHub does not accept an author's own code-ownership as
satisfying the code-owner review requirement. With a single owner and no bypass
actors, PRs opened by @AndreaSucreG cannot be merged — including this one. To
land it, either grant repo-admin bypass on the main ruleset temporarily, or
have @felixcarpena / @raquelyuste approve it while CODEOWNERS is not yet in
effect on main (the file only starts applying once merged).

🤖 Generated with Claude Code

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Note

Low Risk
Repository governance only; no application runtime or data-path changes.

Overview
Adds .github/CODEOWNERS with a * rule pointing at @AndreaSucreG, so pull requests are no longer able to satisfy branch protection’s code-owner review requirement with an empty owner list.

This closes the gap where require_code_owner_review: true on main had no effect because no CODEOWNERS file existed. After merge, every change needs an approval from that owner; the PR notes that GitHub won’t count the author’s own review as the required code-owner review when they are the sole owner.

^{Reviewed by Cursor Bugbot for commit f2b7600. Bugbot is set up for automated code reviews on this repo. Configure here.}

[AndreaSucreG]

Close to use https://github.com/Feverup/platform-terraform/pull/2451