Move runtime assets out of `assets/` to avoid deploy/package conflicts

[valeriu]

Summary

The plugin currently loads its runtime admin files from assets/, but that directory is excluded by .distignore. As a result, the deployed WordPress.org package does not include digitalpilot-admin.js and digitalpilot-admin.css, which leads to 404 errors in Playground and potentially in the published plugin build.

Problem

• digitalpilot.php enqueues admin runtime files from assets/
• .distignore excludes the entire assets/ directory
• The deployed package therefore misses the admin CSS and JS files
• Playground cannot load those files and returns 404 errors

Proposed solution

• Move runtime plugin files from assets/ to static/
• Update all enqueue paths in digitalpilot.php to use static/
• Remove the old assets/ runtime references from the codebase
• Keep WordPress.org-specific files in .wordpress-org/ only

Files to update

• digitalpilot.php

Files to move

• assets/digitalpilot-admin.css -> static/digitalpilot-admin.css
• assets/digitalpilot-admin.js -> static/digitalpilot-admin.js

Expected result

• Admin CSS and JS are included in the WordPress.org deploy artifact
• Playground can load plugin admin assets without 404 errors
• Runtime plugin files are clearly separated from WordPress.org packaging metadata