Track support for randomized storage and `DB_PATH`

[JanJakes]

Track support for randomized SQLite storage and DB_PATH in projects that configure, locate, or copy the database. Existing database paths and older plugin versions should remain supported.

• Randomized SQLite storage — Add randomized SQLite database storage #502
• DB_PATH support — Support DB_PATH as the primary database path constant #512
• WordPress Playground — Support randomized SQLite database storage wordpress-playground#4344
  Covers database path discovery, panels/downloads, and saved Personal WP sites.
• WordPress Playground — Define DB_PATH for explicit SQLite database paths wordpress-playground#4374
  Defines DB_PATH for explicit SQLite database paths.
• WP-CLI wp sqlite — Add support for the new SQLite storage Automattic/wp-cli-sqlite-command#36
  Adds storage discovery for import, export, and table listing.
• WP-CLI wp db — Support DB_PATH for SQLite database commands wp-cli/db-command#351
  Update path discovery to prefer DB_PATH over FQDB.
• WP-CLI tests — Simplify SQLite installation caching wp-cli/wp-cli-tests#367
  Cache and restore SQLite databases with the installation files, including randomized storage.
• WordPress Studio
  Update fixed paths used by native phpMyAdmin and journal-mode handling; check import/export and update bundled dependencies.
• wp-env
  Check compatibility through its Playground runtime and bundled CLI version.
• Playground WordPress plugin
  Check that database exports include the hidden randomized directory and its path metadata.