Refactor overlay drawing and optimize buffer usage

Refactored the overlay rendering logic to use a unified stat line drawing helper, improving code clarity and consistency in text rendering. In SystemMonitor, replaced repeated buffer allocations with a pre-allocated and reusable buffer for counter data, reducing memory allocations and improving performance.

Switch FPS capture to PresentMon, update dependencies

Replaces ETW-based FPS capture with PresentMon integration for improved reliability and portability. Adds PresentMon.exe as an embedded or external dependency, updates related process management logic, and adjusts the FPS calculation pipeline. Updates dependencies in Cargo.toml and Cargo.lock, including downgrading the windows crate for compatibility and adding ctrlc for safe shutdown. Also includes minor bug fixes for HWND/HBRUSH handling and error reporting in the GUI and overlay modules.