chore(logging): Clean up LoggingIntegration - #7248

Description

Get the logging integration into better shape now that Sentry Logs are a first-class feature. The idea is to make Logs the primary feature the integration offers, with capturing breadcrumbs and events an optional add-on.

High-level overview of the changes:

• The integration has to be enabled explicitly by the user.
• Sentry logs related options and features get more generic sounding names.
  • For instance, level (before: sentry_logs_level), ignore_logger (before: ignore_logger_for_sentry_logs) now set the Sentry logs level and Sentry logs denylist, respectively.
  • Existing secondary features with previously generic names get specialized names (level -> breadcrumb_level, ignore_logger -> ignore_logger_for_events).
• Capturing Sentry logs is on by default when the integration is enabled.
• Breadcrumb and event capture is off by default, but can be turned on via an option.
• The capture_sentry_logs option is gone completely. Since logs instrumentation is now on by default, and the level option exists, it was superfluous. Capturing logs can still be opted out of by setting level=None.

Issues

Closes #7246