Refactor FundingRaised with Clean Code improvements

[LediDi060]

Refactored the FundingRaised class to improve readability, maintainability, and reuse:

• Extracted mapRow function – removes duplication (DRY).
• Extracted applyFilters function – separates concerns (SRP), reusable filtering.
• Replaced magic numbers with COLUMNS constants – self-documenting code.
• Extracted CSV filename to FUNDING_FILE constant – easier to maintain and update.

Benefits: cleaner, more readable code; reduced duplication; easier future extensions (e.g., async CSV loading or new filters).

Files changed: node/funding_raised.js