- Updated all instances of device_type from "sound_level_meter" to "slm" across the codebase.
- Enhanced documentation to reflect the new device type standardization.
- Added migration script to convert legacy device types in the database.
- Updated relevant API endpoints, models, and frontend templates to use the new device type.
- Ensured backward compatibility by deprecating the old device type without data loss.
- Created `schedule_list.html` to display scheduled actions with execution status, location, and timestamps.
- Implemented buttons for executing and canceling schedules, along with a details view placeholder.
- Created `unit_list.html` to show assigned units with their status, location, model, and session/file counts.
- Added conditional rendering for active sessions and links to view unit and location details.
