Initial commit: Peak Monitor system tray app with Tau development framework

Peak Monitor is a Linux system tray app that monitors two daily peak
periods (09:00-12:00 and 14:00-18:00, Atlantic/Canary time) and sends
desktop notifications when each period starts and ends.

Files:
- peak_monitor.py: Main application (GTK + AyatanaAppIndicator3)
- peak-monitor.desktop: Desktop entry for autostart
- ROADMAP.md: Development roadmap using Tau as the development framework
- .env.example: Environment variable template (API keys)

Tech stack:
- Python 3 with GTK
- Pillow for tray icons
- libnotify for desktop notifications
- Tau coding agent for development assistance

peak-monitor.desktop

@@ -0,0 +1,9 @@
+[Desktop Entry]
+Type=Application
+Name=Peak Monitor
+Comment=Monitors peak hours (09:00-12:00, 14:00-18:00) Atlantic/Canary
+Exec=python3 /home/ijuanes/CodigoFuente/Timer/peak_monitor.py
+Terminal=false
+Icon=/tmp/peak_monitor_46_204_113.png
+Categories=Utility;
+X-GNOME-Autostart-enabled=true