merge: reconcile master particle-wind work with origin/main redesign

Merged divergent branches (common ancestor a9d87b6). Took origin/main
as base (layer manager, recenter, quit button, GPX tracks, marine
conditions, dark theme, user position layer, active/past track layers)
and layered in particle wind simulation work:

- MapHandler: added setupWindLayer, updateWindLayer, updateWindGridLayer;
  kept their user-pos layer, follow/recenter state, active+past tracks
- WeatherRepository: kept their fetchCurrentConditions, added fetchWindGrid
- MainViewModel: kept their track/marine/summary changes, added windGrid
  StateFlow, loadWindGrid, buildGrid
- MainActivity: kept their full UI (layer picker, quit, recenter, fade
  animations), added particleWindView wiring, weatherLoaded guard,
  windArrow/windGrid observers
- activity_main.xml: took their LinearLayout redesign, added ParticleWindView
  overlay inside ConstraintLayout

https://claude.ai/code/session_01HXPjBsogsJVRwCiekDGkJX

1 files changed, 10 insertions, 4 deletions

diff --git a/test-runner/src/main/kotlin/org/terst/nav/track/TrackRepository.kt b/test-runner/src/main/kotlin/org/terst/nav/track/TrackRepository.kt
index 7953822..85dd2dd 100644
--- a/test-runner/src/main/kotlin/org/terst/nav/track/TrackRepository.kt
+++ b/test-runner/src/main/kotlin/org/terst/nav/track/TrackRepository.kt
@@ -5,22 +5,28 @@ class TrackRepository {
     var isRecording: Boolean = false
         private set
 
-    private val points = mutableListOf<TrackPoint>()
+    private val activePoints = mutableListOf<TrackPoint>()
+    private val pastTracks = mutableListOf<List<TrackPoint>>()
 
     fun startTrack() {
-        points.clear()
+        activePoints.clear()
         isRecording = true
     }
 
     fun stopTrack() {
+        if (isRecording && activePoints.isNotEmpty()) {
+            pastTracks.add(activePoints.toList())
+        }
         isRecording = false
     }
 
     fun addPoint(point: TrackPoint): Boolean {
         if (!isRecording) return false
-        points.add(point)
+        activePoints.add(point)
         return true
     }
 
-    fun getPoints(): List<TrackPoint> = points.toList()
+    fun getPoints(): List<TrackPoint> = activePoints.toList()
+
+    fun getPastTracks(): List<List<TrackPoint>> = pastTracks.toList()
 }