sprint-5: NMEA 2000 stub + Log Book naval básico

vmssailor/runtime/server/nmea2000.py
- PgnFrame dataclass + parsers/encoders para PGNs clave:
  - 127257 Attitude (yaw/pitch/roll en radianes)
  - 127488 Engine Parameters Rapid (RPM, boost, trim)
  - 127489 Engine Dynamic (oil, coolant, alternator, hours)
  - 127505 Fluid Level (tanks)
  - 127508 Battery Status
  - 129025 Position Rapid
- N2KPublisher: tag updates -> PGNs publicados via transport callable
  - Sprint 5: callable de testing/observabilidad
  - Sprint 12+: integracion real con python-can / Actisense / YDWG-02
- N2KSubscriber: inyecta PGNs entrantes y los traduce a tag updates
  - PGN_ATTITUDE -> VESSEL.ROLL_DEG / VESSEL.PITCH_DEG (PGN 127257 = AR-ECDIS source)
  - PGN_ENGINE_RAPID -> ME_INST_{N}.RPM

vmssailor/runtime/server/logbook.py
- LogBook con cadena SHA-256 inmutable (prev_hash -> hash chain)
- LogEntryKind: ENGINE_START, ENGINE_STOP, ALARM_ACTIVE/ACK/CLEARED,
  AUTHORITY_TRANSFER, OVERRIDE, SNAPSHOT, MANUAL
- verify_chain() detecta tampering (bit flip o reescritura)
- query() con filtros por kind/since/until/limit
- EngineLogWriter: auto-detecta start/stop via cruces de umbral RPM
  con persistencia configurable (default 5s)
- SnapshotLogWriter: snapshots periodicos (default 15 min) condicional
  a motor corriendo

API actualizada:
- GET /logbook con filtros
- POST /logbook (entrada manual)
- GET /logbook/verify (integridad de cadena)

RuntimeApp integra todos los servicios. El alarm engine ahora
auto-anota al log book via callback con strong-ref task tracking.

Tests (tests/runtime/, 10 nuevos, total 152/152):
- test_logbook: append, chain, tamper detection, engine start/stop,
  snapshot writer con/sin motor corriendo
- test_nmea2000: PGN encode/decode roundtrip, publisher emits engine
  rapid frames, subscriber handles attitude

152/152 pytest verde, ruff clean.

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

tests/runtime/test_nmea2000.py

@@ -0,0 +1,81 @@
+"""Tests del driver NMEA 2000 (Sprint 5 stub)."""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+from vmssailor.core.enums import Protocol, UnitSI
+from vmssailor.core.tag import Tag
+from vmssailor.runtime.server.nmea2000 import (
+    PGN_ATTITUDE,
+    PGN_ENGINE_RAPID,
+    N2KPublisher,
+    N2KSubscriber,
+    PgnFrame,
+    encode_pgn_attitude,
+    encode_pgn_engine_rapid,
+    parse_pgn_attitude,
+    parse_pgn_engine_rapid,
+)
+from vmssailor.runtime.server.tag_store import TagStore
+
+
+def test_attitude_pgn_roundtrip():
+    data = encode_pgn_attitude(yaw_deg=15.5, pitch_deg=-2.3, roll_deg=8.1)
+    parsed = parse_pgn_attitude(data)
+    assert abs(parsed["roll_deg"] - 8.1) < 0.1
+    assert abs(parsed["pitch_deg"] - (-2.3)) < 0.1
+    assert abs(parsed["yaw_deg"] - 15.5) < 0.1
+
+
+def test_engine_rapid_pgn_roundtrip():
+    data = encode_pgn_engine_rapid(instance=0, rpm=1520.5)
+    parsed = parse_pgn_engine_rapid(data)
+    assert parsed["instance"] == 0
+    assert abs(parsed["rpm"] - 1520.5) < 1.0
+
+
+@pytest.mark.asyncio
+async def test_n2k_publisher_emits_engine_rapid():
+    store = TagStore()
+    store.register_tag(Tag(id="ME_PORT.RPM", unit_si=UnitSI.RPM, protocol=Protocol.MODBUS_RTU, address=1))
+    frames: list[PgnFrame] = []
+    pub = N2KPublisher(store, transport=frames.append)
+    await pub.start(period_s=0.05)
+    try:
+        await store.update("ME_PORT.RPM", 1500.0)
+        await asyncio.sleep(0.2)
+        engine_frames = [f for f in frames if f.pgn == PGN_ENGINE_RAPID]
+        assert len(engine_frames) >= 1
+    finally:
+        await pub.stop()
+
+
+@pytest.mark.asyncio
+async def test_n2k_subscriber_handles_attitude():
+    store = TagStore()
+    store.register_tag(Tag(id="VESSEL.ROLL_DEG", unit_si=UnitSI.DEGREE, protocol=Protocol.INTERNAL))
+    store.register_tag(Tag(id="VESSEL.PITCH_DEG", unit_si=UnitSI.DEGREE, protocol=Protocol.INTERNAL))
+    sub = N2KSubscriber(store)
+    await sub.start()
+    try:
+        data = encode_pgn_attitude(yaw_deg=0.0, pitch_deg=-2.0, roll_deg=5.0)
+        sub.inject_frame(
+            PgnFrame(
+                pgn=PGN_ATTITUDE,
+                source=0,
+                data=data,
+                timestamp=__import__("datetime").datetime.now(__import__("datetime").timezone.utc),
+            )
+        )
+        await asyncio.sleep(0.1)
+        roll = store.get("VESSEL.ROLL_DEG")
+        pitch = store.get("VESSEL.PITCH_DEG")
+        assert roll is not None and roll.value is not None
+        assert abs(float(roll.value) - 5.0) < 0.1
+        assert pitch is not None and pitch.value is not None
+        assert abs(float(pitch.value) - (-2.0)) < 0.1
+    finally:
+        await sub.stop()