feat: prioritize CrossRef DOI resolution in paper search

Add bogus DOI detection and CrossRef verification tests

Make max_retries configurable via command-line argument

Convert Google Scholar tests to integration tests with real HTTP requests

Add test case for SOTOPIA-π paper with Google Scholar parsing

Add verbose logging for 429 retries and Semantic Scholar author verification

Add 429 error handling with retry logic and exponential backoff

Add test for Tomasello book entry to verify Google Scholar parsing works correctly

Address code review feedback - improve regex patterns and ellipsis handling

Add comprehensive tests for Google Scholar HTML parsing

Apply code review feedback: use _remove_curly_braces for authors

Implement curly brace removal and difflib-based title similarity

Fix author extraction to handle comma-separated online formats

Improve author matching with fuzzy logic and update color coding for better UX

Code review fixes: improve conditional expression readability and move imports

Add detailed mismatch information for title and author verification failures

Add Semantic Scholar and web search support, implement author list verification

Remove unused imports and improve URL validation logic

Add test suite for citation verification