Implement Galileo E1B I/NAV navigation decoding

tests/unit/test_lock_detector.py

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+from __future__ import annotations
+
+import numpy as np
+
+from galileo_rx.tracking.lock_detector import LockDetector
+from galileo_rx.types import CorrelatorOutputs
+
+
+def _correlators(phase_rad: float) -> CorrelatorOutputs:
+    prompt = complex(np.exp(1j * phase_rad))
+    return CorrelatorOutputs(0.2 * prompt, 0.5 * prompt, prompt, 0.5 * prompt, 0.2 * prompt)
+
+
+def test_data_lock_detector_ignores_bpsk_transition_but_detects_quadrature_jump() -> None:
+    detector = LockDetector(data_sign_insensitive=True)
+    detector.update(_correlators(0.0))
+    assert detector.update(_correlators(np.pi)).cycle_slip is False
+    assert detector.update(_correlators(np.pi + 0.49 * np.pi)).cycle_slip is True