Release v2.4.0 - Migrate to B8 framework

[sultann]

Summary

Migrates the free plugin off pluginever/framework-plugin and framework-settings onto the B8 framework (byteever/plugin 1.0.0), mirroring the pro plugin's migration (pluginever/wc-serial-numbers-pro#248). The model layer (pluginever/framework-model, Key/Activation models) intentionally stays for a later release, along with the concern regroup and namespace rename which ship next as 2.5.0.

Changes

• Main file follows the wc-starter-plugin flow: Plugin::create() with explicit config and activation hooks via on_activation(); the WooCommerce-missing notice registers through the B8 notices service.
• Plugin extends B8\App; every hook class converted to a B8\Component (Compat and API gate via autoload(); Admin via is_admin). Checkout validation split out of Orders into a Cart component. All source consolidated under includes/ (src/ removed).
• Settings rewritten on B8 SettingsUI with WooCommerce field delegation — raw option names preserved, and the legacy wc_serial_numbers_settings_tabs / wc_serial_numbers_get_settings_{tab} filters keep firing (the pro depends on them). Settings::instance() and save_defaults() kept for the shipped pro installer.
• Installer follows the blueprint pattern, seeds the B8 db version from the legacy option (also fixing the PHP 8.1 version_compare(null) deprecation), and registers the settings component before seeding defaults on activation.
• Custom notices machinery replaced by the B8 notices service (same dismissed-notices option and even the same dismiss AJAX action name). Plugin list action/meta links restored including Go Pro.
• Deprecated functions consolidated into includes/deprecated.php, each tagged; the one live filter that lived there moved into Orders.
• Assets: wp-scripts/webpack replaced with sass + esbuild; sources flattened; the old framework's card/form/layout SCSS vendored as local partials so existing pev-* admin markup keeps its styling; images moved to assets/images.
• A deprecated get_version() shim stays on the Plugin class — the shipped pro 1.4.6 probes it with is_callable(), which the B8 container's __call would otherwise turn into a fatal.
• Minimum WordPress version raised to 6.4; workflows bumped to checkout v6 with a new manual tests workflow.

Verification

• New PHPUnit baseline suite written before the migration and green throughout: 24 tests, 91 assertions.
• The pro plugin's suite (19 tests) passes against this branch, and its CI bootstrap remains compatible with the current wp.org release — all four free/pro version combinations verified.
• composer phpcs clean, php -l clean, assets build, pot regenerated.

[sultann]

Pre-release gates for 2.4.0

Everything below must pass before this ships. The branch itself is verified compatible with pro 1.4.6 at the class/method level (Key::query, Menus static tabs, Settings::instance()->save_defaults(), get_version shim, ListTable all present) — these gates prove it at the behavior level and protect the rollout.

Compatibility

• Shipped-pro zip audit. Grep the pro zips customers actually run (1.4.6, 1.4.5, oldest version with meaningful installs) for references into free (WooCommerceSerialNumbers\ classes, methods called on them, wc_serial_numbers() accessors). Confirm each exists in this branch. The git-head surface is covered; old zips may touch more.
• Extend ContractTest to method level. Assert is_callable for Key::query, Settings::instance + save_defaults, Plugin::get_version, and the Menus static tab callbacks. Class-existence checks alone let a method removal slip through on the @next branch (Key::query is gone there while both shipped pro versions call it) — pinning methods here makes every future branch inherit the guard.

Testing (on the built zip from release.sh, not the repo checkout)

• Matrix smoke with pro 1.4.6: generators screen, keys/stock list tables, tools tabs (import/export/generators must not duplicate — pro removes free's static callbacks by name), settings save + defaults seeding, full order flow delivering keys. Repeat once with the oldest supported pro zip.
• Upgrade path: site on 2.3.4 with real data (keys, activations, settings) → update to 2.4.0. Settings intact, DB version seeds from the old option so historical update routines do not re-run, async update completes. Repeat from 2.3.2.
• Rollback drill: update to 2.4.0, then restore the 2.3.4 zip. Site stays functional with settings intact — proves nothing was migrated-and-deleted.
• Artifact checks: plugin-check clean on the built zip; fresh activation on clean WP + WC at the minimum supported versions.

Rollout

• Release early in the work week, never before a weekend.
• Rollback plan written down before tagging: exact steps to re-point the wp.org stable tag to 2.3.4.
• Watch support forum and fatal reports for 48-72h.
• Pro 1.5.0 ships 3-7 days after, never the same day.
• Changelog: internal architecture migration, no functional changes.

Note: the Key::query removal is a release blocker for #522 (@next), not for this PR — flagged there separately.