### What problem does this PR solve?
This commit refactors the core prompts to decouple the high-level
reasoning from the low-level information extraction. By making
REASON_PROMPT a dedicated strategist that only generates search queries
and re-tasking RELEVANT_EXTRACTION_PROMPT to be a specialized tool for
single-fact extraction, we eliminate redundant information
summarization. This clear separation of concerns makes the overall
reasoning process significantly faster and more precise, as each
component now has a single, well-defined responsibility.
### Type of change
- [x] Performance Improvement
