[NFR]: Extract a neutral boot core from Provider #40

Summary

Provider holds all the boot logic and requires a Phalcon\Mvc\Application. Move the logic that does not need MVC or DI to a new class. MVC behavior does not change.

Current coupling

• The constructor requires Phalcon\Mvc\Application (src/DebugBar/Provider.php:105).
• boot() calls getDI() and getEventsManager() (src/DebugBar/Provider.php:161, :176).
• buildCollectors(), resolveConfig() and resolveRequest() take a DiInterface (src/DebugBar/Provider.php:221, :331, :359).

Proposed direction

• Add a new class with no Phalcon\Mvc or Phalcon\Di imports. It takes:
  • ?Phalcon\Events\ManagerInterface
  • ?Phalcon\Http\RequestInterface
  • ?Phalcon\Config\ConfigInterface
  • the config array
  • optional history parts, so that Provider can pass them
• Move these to the new class: config parsing, the environment and env.strict checks, collector creation, Debug::setBar() and collector subscription.
• The new class exposes the method from [NFR]: Extract a neutral injection method from ResponseListener #39, for hosts with no events manager.
• Provider keeps its constructor, boot(), isAllowed(), registerHistory() and the application:beforeSendResponse attachment. registerHistory() stays because it needs DI.

Notes

• Keep the current MVC result for ConfigCollector (src/DebugBar/Provider.php:269): a DI with no config service creates the collector with a null config.
• Update the provider_config type in DebugBarTypes if the config changes.

Acceptance

• A test boots the new class with no Phalcon\Mvc\Application and no Phalcon\Di\DiInterface.
• The 30 existing ProviderTest tests pass with the same expected results.
• Tests pass with full coverage. phpcs and phpstan pass.

Depends on

• Slice 1 [NFR]: Extract a neutral injection method from ResponseListener #39

Part of

#13