Fix Yahoo Finance 1w Timeframe Error

[merdan-9]

Problem

Users experienced a YFPricesMissingError when selecting the "1w" (weekly) timeframe in the web interface. The error occurred because:

• The web interface was sending interval=1w to Yahoo Finance API
• Yahoo Finance expects interval=1wk for weekly data (not 1w)
• The backend wasn't properly mapping user-facing timeframes to Yahoo Finance intervals

Error Message

YFPricesMissingError('possibly delisted; no price data found (1w 2025-08-26 00:00:00 -> 2025-09-25 11:54:56.758320) (Yahoo error = "Invalid input - interval=1w is not supported. Valid intervals: [1m, 2m, 5m, 15m, 30m, 60m, 90m, 1h, 4h, 1d, 5d, 1wk, 1mo, 3mo]")')

Solution

1. Fixed interval mapping: Added proper mapping from 1w → 1wk and 1mo → 1mo in yfinance_intervals
2. Cleaned up timeframes: Removed redundant timeframes list since interval validation is handled by yfinance_intervals
3. Enhanced display formatting: Added proper display names ("1 week", "1 month") for the new timeframes
4. Added date limits: Configured appropriate date range limits for weekly data (730 days max)