Refactor asset and behaviors management away from swap-oob

Problem/Motivation

We replicated the current core pattern by sending the asset json as an additional element to add to dom and then processing it.

Instead we can use HX-Trigger-After-Settle (see https://htmx.org/headers/hx-trigger/) to send the json and trigger it to be processed

Proposed resolution

1. Improve the code architecture of htmx-assetManagement.js and htmx-drupalBehaviors.js based on prior feedback.
2. Change HtmxResponseAttachmentsProcessor to add a HX-Trigger-After-Swap header. In the header pass the event htmxDrupalAssetsAttached along with the JSON encoded asset arrays.
3. Listen for and process the custom event in htmx-assetManagement.js.