Use wp_script_attributes to add attributes to the BA script

[Woldbye]

Use the wp_script_attributes filter (WP 5.7+) to add data attributes to the tracking script tag, replacing the previous script_loader_tag + str_replace approach. This operates on the attributes array before HTML generation, as recommended by the WordPress plugin reviewer.

Changes

• Replace script_loader_tag filter with wp_script_attributes filter for adding data-* attributes to the tracker script
• Refactor add_tracker_script_attributes() from HTML string manipulation to array-based attribute injection
• Update all attribute-related tests to use array input/output instead of HTML string assertions