Sink: Amazon S3

[gwaramadze]

Add FileSink with pluggable destinations

This PR introduces a new design for the FileSink that separates storage concerns from data serialization. The main changes include:

Key Changes

• Refactored FileSink to use a pluggable destination system
• Created a base Destination class to define the storage interface
• Added two concrete implementations:
  • LocalDestination for writing to local filesystem
  • S3Destination for writing to Amazon S3 buckets
• Split documentation into separate pages for local and S3 storage

Benefits

• Cleaner separation of concerns between data serialization and storage
• Easier to add new storage backends
• More flexible configuration options for each destination type
• Better error handling with specific exception types for S3

Implementation Details

• FileSink now accepts a destination parameter that defaults to LocalDestination
• Each destination implements common interface methods: write(), set_directory(), etc.
• S3 implementation includes proper AWS credential handling and bucket validation
• Local implementation supports both append and create modes for compatible formats

Documentation

• Created separate documentation pages for local and S3 storage options
• Updated examples to show both local and S3 configurations