Refactor random data sender into CLI with Measurement dataclass

[nk25719]

Motivation

• Modernize and clean up the old procedural script to be Python 3 friendly and easier to test and reuse.
• Remove import-time socket activity and global mutable state so the module can be imported safely.
• Make PIRDS measurement encoding explicit and maintain backward compatibility with existing callers.

Description

• Replace the ad-hoc script with a documented CLI module and a frozen @dataclass Measurement that implements as_bytes() for the 12-byte PIRDS frame.
• Extracted focused helpers: terminate_with_newline, random_measurement, send_random_measurements, and parse_args, and added a main() entry point guarded by if __name__ == "__main__".
• Keep compatibility wrappers asBytes() and printMeasurement() that delegate to the new snake_case methods.
• Add constants for DEVICE_TYPES/MEASUREMENT_TYPES and a DEFAULT_SAMPLE_COUNT to replace many implicit globals.

Testing

• Ran python3 -m compileall data_server which succeeded.
• Executed inline assertions that instantiate Measurement('T','B',25,123456789,-7) and verified m.asBytes() == m.as_bytes(), the 13-byte payload length with newline, header bytes, and that the measurement value decodes as -7, which all passed.
• Confirmed the module imports without executing socket activity and the CLI entrypoint returns SystemExit(main()) when run as a script.

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Codex Task