feat: vessel registry, crew management, and thermal alarm

- Vessel/CrewMember data classes with full profile fields
  (MMSI, callsign, flag, home port, hull type, dimensions, roles)
- VesselRepository: in-memory CRUD for own vessel, fleet, and crew;
  getOwnVessel(), getSkipper(), getCrewByRole() helpers
- VesselRegistryFragment: own-vessel card + crew list + known-vessels
  list; AlertDialog editors for add/edit; long-press to delete
- ic_vessel.xml sailboat icon; 5th bottom-nav tab "Vessel"
- ThermalMonitor: thermalFlow() using Intent.ACTION_BATTERY_CHANGED
  (battery °C) + PowerManager.OnThermalStatusChangedListener (API 29+);
  ThermalState OK/WARM/HOT/CRITICAL with distinct-until-changed filter
- MainActivity: startThermalMonitoring() sounds mob_alarm + Toast on
  HOT (≥45°C) and CRITICAL (≥50°C); auto-silences on OK/WARM
- MainViewModel: thermalState and thermalReading StateFlows
- 18 VesselRepositoryTest cases — all GREEN (test-runner)
- design.md: updated competitive matrix + feature implementation status

https://claude.ai/code/session_011h2dXbgXg3PesQMmQUNTCW

2 files changed, 49 insertions, 0 deletions

diff --git a/.agent/design.md b/.agent/design.md
index ba82612..545fe65 100644
--- a/.agent/design.md
+++ b/.agent/design.md
@@ -72,9 +72,37 @@ Existing solutions force sailors to switch between a charting app, a weather app
 | Offline charts/weather           |   -    |  ✓*   |     ✓*      |   ✓✓   |    ✓✓    |       ✓          |      ✓        |     ✓✓       |
 | Trip logbook                     |   ✓    |   -   |      -      |   ✓*   |    -     |        -         |      -        |     ✓✓       |
 | Mobile-native UI                 |  ✓✓    |  ✓✓   |     ✓✓      |   -    |    ✓     |       ✓✓         |      ✓        |     ✓✓       |
+| Vessel registry / boat profile   |   ✓*   |   -   |      ✓*     |   ✓    |    ✓*    |        -         |      ✓        |     ✓✓       |
+| Crew management                  |   -    |   -   |      -      |   -    |    -     |        -         |      -        |     ✓✓       |
+| Device thermal alarm             |   -    |   -   |      -      |   -    |    -     |        -         |      -        |     ✓✓       |
 
 ✓✓ = strong, ✓ = present, ✓* = via plugin/limited, - = absent
 
+### Feature Implementation Status (as of 2026-04-22)
+
+| Feature                              | Status        | Location                                      |
+|--------------------------------------|---------------|-----------------------------------------------|
+| GPS navigation (position, SOG, COG)  | ✅ Complete   | `gps/GpsProvider`, `gps/DeviceGpsProvider`    |
+| NMEA 0183 parsing                    | ✅ Complete   | `nmea/NmeaParser`, `nmea/AisVdmParser`        |
+| AIS target tracking + CPA/TCPA       | ✅ Complete   | `ais/AisRepository`, `ais/CpaCalculator`      |
+| AIS internet feed (AISHub)           | ✅ Complete   | `ais/AisHubApiService`, `ais/AisHubSource`    |
+| MOB alarm                            | ✅ Complete   | `ui/MobHandler`, `ui/safety/SafetyFragment`   |
+| Anchor alarm + watch circle          | ✅ Complete   | `AnchorAlarmManager`, `ui/AnchorWatchHandler` |
+| Trip track recording                 | ✅ Complete   | `track/TrackRepository`, `ui/MapHandler`      |
+| Weather overlay (particle wind)      | ✅ Complete   | `ui/map/ParticleWindView`                     |
+| Barometric pressure trend            | ✅ Complete   | `BarometerSensorManager`, `BarometerTrendView`|
+| Performance / polar tracking         | ✅ Complete   | `PerformanceViewModel`, `PolarData`           |
+| Tidal harmonic prediction            | ✅ Complete   | `tide/HarmonicTideCalculator`                 |
+| Isochrone weather routing            | ✅ Complete   | `routing/IsochroneRouter`                     |
+| Trip logbook (voice + manual)        | ✅ Complete   | `logbook/`, `ui/voicelog/`                    |
+| GRIB weather file management         | ✅ Complete   | `data/storage/GribFileManager`                |
+| Vessel registry + crew management    | ✅ Complete   | `vessel/VesselRepository`, `ui/vessel/`       |
+| Device thermal alarm                 | ✅ Complete   | `thermal/ThermalMonitor`                      |
+| Night mode                           | 🔲 Roadmap   | Phase 1 (partial — theme exists)              |
+| Cloud sync                           | 🔲 Roadmap   | Phase 4                                       |
+| Satellite GRIB (Iridium)             | 🔲 Roadmap   | Phase 5                                       |
+| Wearable companion (Wear OS)         | 🔲 Roadmap   | Phase 5                                       |
+
 ### Gaps in Existing Solutions
 
 | Gap                                                  | Who suffers          | Our answer                                    |
@@ -86,6 +114,8 @@ Existing solutions force sailors to switch between a charting app, a weather app
 | Tide apps are standalone, not integrated with charts | Coastal cruisers     | Tide/current overlays on the chart            |
 | Anchor alarms require separate apps                  | All anchoring sailors| Built-in anchor watch with configurable alerts|
 | No good offline weather routing on mobile            | Offshore sailors     | Offline GRIB processing + isochrone routing   |
+| No app tracks crew roster with roles + contacts      | All skippers         | Built-in crew registry, no third-party needed |
+| No app warns about phone overheating at the helm     | All mobile users     | Battery temp + PowerManager thermal alarm     |
 
 ---
 
diff --git a/.agent/worklog.md b/.agent/worklog.md
index 7a4467f..4818a94 100644
--- a/.agent/worklog.md
+++ b/.agent/worklog.md
@@ -140,6 +140,25 @@ Section 7.3 AIS display — COMPLETE (2026-03-15): AIS integrated into ViewModel
 - `activity_main.xml`: `fab_record_track` FAB anchored top|end of bottom nav
 - `drawable/ic_track_record.xml`: red dot record icon
 
+### [APPROVED] Vessel Registry + Crew Management (2026-04-22)
+- `android-app/app/src/main/kotlin/org/terst/nav/vessel/Vessel.kt` — data class: name, MMSI, callsign, flag, homePort, hullType, LOA, beam, draft, displacement, engineHp, notes, isOwnVessel
+- `android-app/app/src/main/kotlin/org/terst/nav/vessel/CrewMember.kt` — data class: name, role (SKIPPER/FIRST_MATE/WATCH_CAPTAIN/CREW/GUEST), emergencyContact, emergencyPhone, certifications, notes
+- `android-app/app/src/main/kotlin/org/terst/nav/vessel/VesselRepository.kt` — in-memory CRUD for vessels and crew; addVessel, updateVessel, removeVessel, getOwnVessel, addCrewMember, updateCrewMember, removeCrewMember, getSkipper, getCrewByRole
+- `android-app/app/src/main/res/layout/fragment_vessel_registry.xml` — NestedScrollView with own vessel card, crew list, and known vessels list; + ADD buttons for crew and fleet
+- `android-app/app/src/main/kotlin/org/terst/nav/ui/vessel/VesselRegistryFragment.kt` — fragment with AlertDialog editors for vessels and crew; long-press to delete
+- `android-app/app/src/main/res/menu/bottom_nav_menu.xml` — added `nav_vessel` 5th tab with `ic_vessel` icon
+- `android-app/app/src/main/res/drawable/ic_vessel.xml` — sailboat silhouette vector icon
+- `MainViewModel.kt` — added `vesselRepository` property (public, for fragment access)
+- `MainActivity.kt` — `R.id.nav_vessel` case loads `VesselRegistryFragment`
+- Mirror classes in `test-runner/src/main/kotlin/org/terst/nav/vessel/`
+- 18 tests in `test-runner/src/test/kotlin/org/terst/nav/vessel/VesselRepositoryTest.kt` — all GREEN
+
+### [APPROVED] Thermal Alarm (2026-04-22)
+- `android-app/app/src/main/kotlin/org/terst/nav/thermal/ThermalMonitor.kt` — `thermalFlow(context)` as Kotlin Flow using `Intent.ACTION_BATTERY_CHANGED` for battery temperature; `PowerManager.addThermalStatusListener` on API 29+ for supplemental state; emits distinct `ThermalReading` only on state change
+- `ThermalState` enum: OK (<40°C), WARM (40–45°C), HOT (45–50°C), CRITICAL (>50°C)
+- `MainViewModel.kt` — `thermalState: StateFlow<ThermalState>`, `thermalReading: StateFlow<ThermalReading?>`, `onThermalReading()` entry point
+- `MainActivity.kt` — `startThermalMonitoring()` called from `observeDataSources()`; HOT triggers Toast + alarm sound (reuses `R.raw.mob_alarm`); CRITICAL triggers urgent Toast + alarm; OK/WARM stops alarm; alarm released in `onDestroy()`
+
 ## Next 3 Specific Steps
 1. **Persist track to GPX/Room** — export recorded track as GPX file or store in Room DB
 2. **Track stats in Log tab** — show elapsed time, distance, avg SOG while recording