[FEAT] DPL: use Signposts everywhere in DataProcessingDevice

[ktf]

[FEAT] DPL: use Signposts everywhere in DataProcessingDevice

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• [DRAFT] DPL: Introduce calibration mode #12723 (3 commits)
• -> [FEAT] DPL: use Signposts everywhere in DataProcessingDevice #12868 (5 commits)

[github-actions]

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