refactor(functions-utils): replace dependencies with native APIs

[43081j]

This replaces the following in functions-utils:

• cpy with fs.cp, still filtering out junk
• path-exists with fs.access and, in tests, existsSync
• sort-on with a basic sort function
• tmp-promise with fs.mkdtemp and randomUUID

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📝 Walkthrough

Summary by CodeRabbit

• Bug Fixes

  • Improved function copying by excluding unwanted system files.
  • Added clearer errors when a source path cannot be found.
  • Improved handling when replacing existing destination files.

• Maintenance

  • Updated temporary-directory handling for more reliable test execution.
  • Simplified file-copying and function-list ordering behavior.

Walkthrough

Replaces cpy, path-exists, tmp-promise, and sort-on usage in functions-utils. The add function now uses fs.access and fs.cp, filtering junk files during recursive copies. Test helpers use Node.js temporary-directory APIs, while tests use native existence and file-copy operations plus a local sorting helper.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Possibly related PRs

• netlify/build#7107: Refactors related filesystem copy and cache logic to use fs.cp and junk-file filtering.

Suggested reviewers: serhalp

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title is concise and accurately summarizes the main change: replacing functions-utils dependencies with native APIs.
Description check	✅ Passed	The description covers the dependency replacements and checklist, but it is missing the required Fixes #issue reference and explicit motivation.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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🧪 Generate unit tests (beta)

• Create PR with unit tests

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[github-actions]

e18e dependency analysis

No dependency warnings found.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@packages/functions-utils/src/main.ts`:
- Around line 14-28: Ensure the destination directory returned by getDist() is
created before the fs.cp call in the copy flow. Add the directory-creation step
after validating dist and before copying src, while preserving the existing
recursive copy, force, and filter options.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 3191968d-7aa6-4408-87d8-06b91e101428

📥 Commits

Reviewing files that changed from the base of the PR and between af94ccf and 7ee8dd4.

⛔ Files ignored due to path filters (1)

• package-lock.json is excluded by !**/package-lock.json

📒 Files selected for processing (4)

• packages/functions-utils/package.json
• packages/functions-utils/src/main.ts
• packages/functions-utils/tests/helpers/main.ts
• packages/functions-utils/tests/main.test.ts

🔗 Linked repositories identified

CodeRabbit considers these linked repositories for cross-repo context during reviews:

• netlify/blueprints (manual)

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commit: 7ee8dd4