Fix volume control for Electron apps (Discord, Brave) & Crash Fixes on macOS Tahoe

This PR addresses critical volume control issues and crashes, specifically tested on **macOS Tahoe 26.0.1**. **Environment & Context:** * **OS:** macOS Tahoe 26.0.1 * **Status Before Fix:** System sounds, general computer audio, and Google Chrome were working correctly. However, volume control was completely non-functional for **Discord** and **Brave Browser**. * **Fix Verification:** This patch successfully restores volume control for Discord (by targeting the correct renderer process) and resolves the more complex broadcasting issues required for Brave Browser. **Technical Changes:** 1. **Process Broadcasting:** Added a mechanism to broadcast volume changes to all related processes (fixing Brave/Discord helpers not responding to the main app slider). 2. **Crash Protection:** - Fixed a crash caused by passing `nullptr` as BundleID to the driver (replaced with a safe placeholder). - Added `try-catch` blocks and safe memory management around process iteration to prevent app crashes during volume adjustments. 3. **UI Cleanup:** Improved filtering to show only the main "Discord" and "Brave Browser" apps in the list, hiding unnecessary "Helper/GPU" processes while maintaining control over them.