v0.5.0 - Resilient Batch Indexing and SDK/CLI Parity

Added

• Structured batch indexing result models for SDK consumers:
  • BatchIndexResult (inputs, discovered/indexed/skipped sources, failures)
  • BatchIndexFailure (source_url, stage, error_message)
• New AudioRAGPipeline.index_many(inputs, force=False, raise_on_error=True)
  contract that returns structured batch outcomes and supports tolerant mode
  (raise_on_error=False) for partial-failure reporting.

Changed

• Core indexing boundary now performs source discovery for SDK calls too:
  • index(url) routes through discovery-backed batch indexing
  • Playlist/channel URLs and local directories are processed per source with
    independent state/resume semantics.
• Batch indexing error handling is now resilient across exception types:
  non-PipelineError failures are normalized and captured in batch results,
  while strict mode still raises with clear context.
• CLI audiorag index now uses the unified pipeline batch path and reports
  aggregate batch outcomes (indexed/skipped/failed) with per-source failures.

Documentation

• Updated README and docs (quickstart, api-reference) to reflect:
  • SDK/CLI behavior parity for discovery-backed indexing
  • raise_on_error behavior and structured batch results
  • Updated batch indexing examples and output expectations