Implement Storage Context with Driver-Agnostic Design (Local File Storage as Initial Implementation)

[iammuho]

Related issue: #19

This PR lays the foundation for a driver-agnostic storage subsystem in NatterNet by introducing StorageContext and DriverContext interfaces. The design allows for seamless extension with various storage drivers in the future.

Changes:
New Interfaces:

• DriverContext defines methods that any storage driver must implement (Get, Put, Delete, List).
• StorageContext serves as the entry point for the storage subsystem and delegates operations to the underlying driver.

File Storage Driver:

• As an initial implementation, a local file storage driver is added.
• Implements the DriverContext interface and contains methods to manage local files (Get, Put, Delete, List).

Factory Method:

• NewStorage factory method to create a new StorageContext instance.
• Currently supports only local file storage; can be easily extended to include other drivers.