Settings: Make all tabs filterable

[obenland]

Updates the activitypub_admin_settings_tabs filter to not only add tabs, but control the tabs that get displayed in general.

Proposed changes:

• Passes all settings tabs to the filter.
• Adds doing it wrong notice if somehow we end up with 0 tabs and falls back to settings.
• Determines default tab based on the order in the settings_tabs array.

Other information:

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

Testing instructions:

• Go to Settings > Activitypub and navigate through the settings tabs.
• Activate/deactivate Welcome and Advanced settings tab, make sure they still work.

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

Plugins now have full control over which Settings tabs are shown in Settings > Activitypub.

[Copilot]

Pull Request Overview

This PR refactors the settings tabs logic to let plugins fully control which tabs appear, adds a fallback when no tabs are provided, and chooses the default tab from the filtered list.

• Passes the complete $settings_tabs array into the activitypub_admin_settings_tabs filter
• Introduces a _doing_it_wrong fallback and default‐"Settings" tab if no tabs are returned
• Computes the default selected tab based on the first key in the filtered tabs

Comments suppressed due to low confidence (3)

includes/wp-admin/class-settings.php:307

• [nitpick] The variable name $settings_tab is easily confused with $settings_tabs. Consider renaming it to something like $default_settings_tab or $settings_tab_item to improve clarity.

$settings_tab      = array(

includes/wp-admin/class-settings.php:347

• Add a unit or integration test that simulates the activitypub_admin_settings_tabs filter returning an empty array to ensure the fallback logic and _doing_it_wrong notice are exercised correctly.

if ( empty( $settings_tabs ) ) {

includes/wp-admin/class-settings.php:344

• Expand the docblock above the apply_filters call to include a @return array annotation that describes the expected shape of the returned tabs (e.g., an associative array mapping tab slugs to arrays with 'label' and 'template' keys).

* @param array $settings_tabs The tabs to display.