Add destination profile & strict true-peak option with runtime scoring overrides and UI updates

[MLyte]

Motivation

• Provide destination-specific scoring behavior (e.g. streaming, club, archive) and an option to enforce stricter true-peak caps at runtime.
• Surface the new options in the UI so users can select a destination profile and enable a strict true-peak mode.

Description

• Added destination_profile and strict_true_peak to WorkerRequest and threaded these through the worker to EngineService.optimize in src/optimaster/gui.py and src/optimaster/service.py.
• Introduced DESTINATION_SCORING_OVERRIDES and a _runtime_scoring_config helper in EngineService to apply destination-specific overrides and tighten true-peak limits using dataclasses.replace before scoring.
• Updated the GUI to include a destination profile QComboBox, a QCheckBox for strict true-peak, minor diagnostic and UX text improvements, and additional candidate detail lines (delta vs source and a listening checklist).
• Added automated tests in tests/test_service_profiles.py that verify destination overrides and strict true-peak capping behavior.

Testing

• Ran the new unit tests with pytest tests/test_service_profiles.py which passed.
• Ran the full test suite with pytest -q and observed no regressions in the test run related to the changes.

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Codex Task