New: Improve settings panel search and add web push notification controls

[RabbiIslamRony]

Summary

• redesign active gateways as a dedicated Payment Methods card with switch controls
• improve settings search indexing for section titles and checkbox options with precise section/field highlighting
• make the settings search palette viewport-safe on responsive screens
• fix mobile toggle sizing and highlight spacing in the redesigned settings panel
• rename the fallback settings menu label from Needs Design to Other
• fix Elementor Theme Builder navigation from Directorist settings by encoding return_to

Verification

• php -l includes/classes/class-settings-panel.php
• git diff --check on staged source files
• Agent Browser: Payment Methods search/highlight flow
• Agent Browser: settings search palette at 1440x750, 767x750, and 480x750
• Agent Browser: Elementor Theme Builder opens from Directorist settings
• Agent Browser: sidebar shows Other and no longer shows Needs Design

Notes

• Built settings-manager admin assets are included from the active watcher.
• No settings migration is required; saved option keys and storage remain unchanged.