Adds a user-configurable "Failed Services" alert that notifies when any
tracked systemd service enters the failed state, and again when all services
recover.
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Signed-off-by: Martin Stenröse <martin@stenrose.se>
Co-authored-by: henrygd <hank@henrygd.me>
- Report battery data for individual devices
- Select a representative battery for legacy fields and alerts
- Average named battery data independently
- Display multiple batteries in system charts
- Add cross-platform coverage and transport tests
