feat: add 5 deterministic rules (IMU outliers/watchdog, USBL SNR/spike, battery_low)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/cosma_log_analyzer/rules/__init__.py

@@ -0,0 +1,34 @@
+"""Deterministic rules v0.
+
+Adding a new rule = subclass Rule, register it in `ALL_RULES`, add a test.
+"""
+from __future__ import annotations
+
+from .base import Rule
+from .battery_low import BatteryLowRule
+from .imu_outliers import ImuOutliersRule
+from .usbl_distance_spike import UsblDistanceSpikeRule
+from .usbl_snr_low import UsblSnrLowRule
+from .watchdog_imu import WatchdogImuRule
+
+
+def all_rules() -> list[Rule]:
+    """Default rule set, instantiated with env/default thresholds."""
+    return [
+        ImuOutliersRule(),
+        WatchdogImuRule(),
+        UsblSnrLowRule(),
+        UsblDistanceSpikeRule(),
+        BatteryLowRule(),
+    ]
+
+
+__all__ = [
+    "Rule",
+    "ImuOutliersRule",
+    "WatchdogImuRule",
+    "UsblSnrLowRule",
+    "UsblDistanceSpikeRule",
+    "BatteryLowRule",
+    "all_rules",
+]