This pull request introduces a new feature to the Switcher client: automatic refresh of the API authentication token before expiration. It also refactors internal scheduling logic to support this feature and updates configuration, documentation, and tests accordingly.

New Feature: Automatic Token Refresh

• Adds support for automatically refreshing the API token before it expires, controlled by a new configuration property.

Configuration and Documentation Updates

• Adds the switcher.autorefreshtoken property to the configuration system and documents it in README.md. [1] [2] [3] [4]
• Updates the ContextBuilder and SwitcherConfig classes to support and propagate the new property. [1] [2] [3] [4] [5]

Scheduling and Executor Service Refactor

• Refactors executor services to separate snapshot and token refresh workers, and introduces new methods to manage the lifecycle of these workers. [1] [2] [3] [4] [5] [6]

Core Logic for Token Auto-Refresh

• Implements scheduling logic in ClientRemoteService to refresh the authentication token shortly before it expires, with error handling and logging. [1] [2] [3] [4]

Other Updates

• Bumps the project version to 2.6.0-SNAPSHOT.
• Minor test refactoring for improved clarity and reuse. [1] [2] [3] [4] [5]