0.1.21 Patch

1. Continue to optimize the logic for NPCs (Institutional Investors, Retail Investors) and fix the issue of endless decline after selling.
2. Change the unit for total shares and tradable shares from "share" to "lot", where 1 lot = 100 shares.
3. When price tracking is enabled, manually editing the price will automatically cancel price tracking.
4. Fixed the issue where quantity could not be manually edited after enabling price tracking.