Feature/multi-asset-allocation

[Mehranmzn]

Description

• add a standalone MultiAssetAllocationAgent that takes only a USD budget (plus optional styles) and outputs allocations across stocks/ETFs/crypto for 1w/1m/1y horizons,
  including rationales and sample tickers
• expose the planner through FinancialAdvisor and the CLI (--multi-asset-budget, optional --multi-asset-strategies, --multi-asset-pdf-path) so the plan can be
  generated independently of the existing workflow
• introduce MultiAssetPDFReportWriter to render the allocation plan as a PDF, and extend the advisors’ console printer plus docs/tests around the new flows
• persist scraped news to DuckDB via NewsRepository, exclude open-access feeds from LLM input, and embed allocation charts into the existing channel PDF report

Type of Change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactoring
• Test addition/modification

Testing

• Unit tests pass locally: pytest tests/unit/test_multi_asset_agent.py tests/unit/test_news_repository.py tests/unit/test_channels.py
• Integration tests pass locally
• New tests added for new functionality (multi-asset agent + PDF + news repo)
• All existing tests still pass

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my feature works
• New and existing unit tests pass locally with my changes
• Pre-commit/ruff hooks pass

Security Considerations

• No security concerns
• Security review required
• Security documentation updated