fix: only count previously approved normal comments for auto-approval

[faisalahammad]

Fixes #3579

Proposed changes:

When a remote account likes or reposts a post, the plugin stores that as an approved comment (with a non-default comment type such as like or repost). The pre_comment_approved filter then looked up whether the same author already had an approved comment, but did not filter by comment type. So that approved reaction counted as a "previously approved comment", and it auto-approved the same account's later normal replies even when "Comment author must have a previously approved comment" was enabled.

The fix mirrors what WordPress core's wp_allow_comment() does: it only counts prior approved comments of type comment, so reactions no longer leak approval to real replies. An account that previously replied normally is still auto-approved.

Other information:

• Have you written new tests for your changes, if applicable?

Added test_pre_comment_approved_ignores_reactions() in tests/phpunit/tests/includes/class-test-comment.php, which inserts an approved like from a remote actor and verifies that a normal reply from the same actor stays held for moderation.

Testing instructions:

Because $comment_previously_approved needs to affect published replies, the trickiest part is setting up the scenario:

• Enable "Comment author must have a previously approved comment" (Settings -> Discussion).
• From a remote Mastodon account that has never commented on your site, like one of your posts (auto-approve Likes must be enabled).
• From that same account, reply with a normal comment on another post.
• The reply should land in Comments as pending (held for moderation), not approved.

Before this fix, that reply was auto-approved, because the account's previous Like was treated as a previously approved comment. A remote account that previously submitted a normal comment should still be auto-approved.

Changelog entry

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Changelog Entry Details

Significance

• Patch
• Minor
• Major

Type

• Added - for new features
• Changed - for changes in existing functionality
• Deprecated - for soon-to-be removed features
• Removed - for now removed features
• Fixed - for any bug fixes
• Security - in case of vulnerabilities

Message

Fixed normal replies from distant accounts sometimes being auto-approved just because that account had previously liked or reposted a post.