Merge origin/main — unite all work onto one branch

Brings in dev log (NavLogger), UnitPrefs, MapLayerManager, HUD views,
conditions throttling, track save/load pipeline, improved ParticleWindView
(antimeridian-aware, dynamic particle count), Snackbar error surfacing,
and all other main-branch work from the prior session.

Combined with master's hardware source flags, vessel registry, crew
management, thermal alarm, CPA collision alerts, and track stats.

Also documents primary branch policy in CLAUDE.md and .agent/config.md:
all work merges to main, never master.

https://claude.ai/code/session_011h2dXbgXg3PesQMmQUNTCW

1 files changed, 59 insertions, 0 deletions

diff --git a/docs/superpowers/specs/2026-04-03-map-interaction-design.md b/docs/superpowers/specs/2026-04-03-map-interaction-design.md
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+# Map Interaction Design
+_2026-04-03_
+
+## Overview
+
+Enable free map pan/zoom while keeping GPS auto-follow as the default. When the user gestures on the map, the UI hides and a Recenter button appears. Tapping Recenter restores auto-follow and the full UI.
+
+## State
+
+A single `isFollowing: Boolean` flag owned by `MapHandler`. Starts `true`. This is the only piece of new state.
+
+## Entering Manual Mode
+
+`MapLibreMap.addOnCameraMoveStartedListener` fires with `REASON_API_GESTURE` when the user initiates a pan, pinch-zoom, or rotate. On that event:
+
+- `MapHandler.isFollowing` → `false`
+- `MapHandler` emits via a new `StateFlow<Boolean> isFollowing` exposed to MainActivity
+- `MapHandler.centerOnLocation()` becomes a no-op while `!isFollowing` — GPS updates still arrive, last position is stored
+
+## Returning to Auto-Follow
+
+`fab_recenter` click handler:
+
+- Calls `MapHandler.recenter()` — sets `isFollowing = true`, calls `centerOnLocation(lastLat, lastLon)`
+- `isFollowing` StateFlow emits `true` → MainActivity restores UI
+
+## UI Changes
+
+### New element: `fab_recenter`
+
+- Pill-shaped button (`wrap_content` width, 40dp height, 20dp corner radius)
+- Label: "⊙ Recenter"
+- Position: centered horizontally, `24dp` above the bottom of the map `ConstraintLayout`
+- `android:visibility="gone"` by default
+- Elevation: 20dp (above the instrument sheet)
+
+### Visibility toggling (MainActivity)
+
+When `isFollowing` → `false`:
+- Fade out (alpha 0, 150ms): `instrument_bottom_sheet`, `bottom_navigation`, `fab_mob`, `fab_record_track`
+- Show `fab_recenter` (visibility VISIBLE, fade in 150ms)
+
+When `isFollowing` → `true`:
+- Hide `fab_recenter` (fade out 150ms, then GONE)
+- Fade in (alpha 1, 150ms): `instrument_bottom_sheet`, `bottom_navigation`, `fab_mob`, `fab_record_track`
+
+## Files to Change
+
+| File | Change |
+|------|--------|
+| `MapHandler.kt` | Add `isFollowing` StateFlow, `lastLat`/`lastLon` storage, `recenter()`, guard in `centerOnLocation()`, register `OnCameraMoveStartedListener` |
+| `activity_main.xml` | Add `fab_recenter` pill button |
+| `MainActivity.kt` | Observe `mapHandler.isFollowing`, animate UI in/out, wire `fab_recenter` click |
+
+## Out of Scope
+
+- Tapping the map (without gesture) to restore UI — not requested
+- Timeout to auto-restore UI — not requested
+- Zoom-level persistence across recenter — not requested