feat: initial release — SRT Streamer v1.0.0

Cross-platform Electron + React + FFmpeg desktop app for sending
multiple SRT streams simultaneously.

Features:
- Multiple simultaneous SRT output streams
- Video sources: desktop, window capture, cameras, capture cards
- Audio sources: microphones, system loopback, sound cards
- H.264 encoding with HW acceleration (NVENC/QSV/AMF/VideoToolbox)
- SRT modes: caller / listener / rendezvous
- Frame profile presets (4K, 1080p, 720p, 480p, 360p)
- Tolbek SRT receiver with configurable mode
- System tray: minimize-to-tray, exit confirmation dialog
- Portable build via electron-builder

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

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+*.bat text eol=crlf
+*.cmd text eol=crlf