fix: switch auto-fix URL grouping to whitelist approach

[holtvogt]

Previously, new opportunity types defaulted to URL-grouped behavior, which silently dropped suggestions without URL data. Now types must explicitly opt-in to URL grouping, making ungrouped the safe default.

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[Copilot]

Pull request overview

This PR fixes a critical issue with auto-fix suggestion handling by switching from a blacklist to a whitelist approach for URL grouping. Previously, new opportunity types defaulted to URL-grouped behavior, which could silently drop suggestions lacking URL data. The new approach makes ungrouped the safe default, requiring explicit opt-in for URL grouping.

Key Changes

• Inverted the logic from AUTOFIX_UNGROUPED_OPPTY_TYPES (blacklist) to URL_GROUPED_OPPORTUNITY_TYPES (whitelist)
• Added comprehensive test coverage for unknown opportunity types to validate the new default behavior
• Updated test descriptions to reflect the correct behavior

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/controllers/suggestions.js	Replaced blacklist with whitelist containing only 4 types that require URL grouping (alt-text, broken-internal-links, high-organic-low-ctr, meta-tags)
test/controllers/suggestions.test.js	Added test for unknown opportunity types defaulting to ungrouped behavior; fixed test description for form-accessibility test

The changes are well-implemented with clear documentation and appropriate test coverage. The logic inversion is correct, and the whitelist properly includes only the types that need URL-based grouping. No issues were found during this review.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[github-actions]

This PR will trigger a patch release when merged.