Fix Recenter bleed-through; drop noisy speed events; track detail as bottom sheet

Recenter button was reappearing over overlays because the isFollowing
flow kept calling fadeIn(fabRecenter) even when an overlay was visible.
Added overlayShowing flag — the flow skips FAB updates while an overlay
is shown. hideOverlays() now correctly restores fabRecenter visibility
based on the actual following state instead of just resetting alpha.

Speed up/Slow down events fired on every 1.5 kt GPS jitter, flooding
the log with noise. Removed the detection loop entirely — no reliable
motor on/off signal is available from GPS alone.

TrackDetailSheet converted from a full-screen Fragment to a
BottomSheetDialogFragment: opens at half-screen height so the track
route is visible on the map behind it, draggable to full height, 20%
background dim. SavedTracksFragment now calls hideOverlays() then
sheet.show() instead of fragment-replacing the overlay container.

https://claude.ai/code/session_01YUbuZNDAoLea4cf9UGQ9qn

1 files changed, 7 insertions, 0 deletions

diff --git a/android-app/app/src/main/res/layout/layout_track_detail_sheet.xml b/android-app/app/src/main/res/layout/layout_track_detail_sheet.xml
index 6a2ba50..97b1da8 100644
--- a/android-app/app/src/main/res/layout/layout_track_detail_sheet.xml
+++ b/android-app/app/src/main/res/layout/layout_track_detail_sheet.xml
@@ -6,6 +6,13 @@
     android:orientation="vertical"
     android:background="?attr/colorSurface">
 
+    <!-- Drag handle -->
+    <View
+        android:layout_width="36dp"
+        android:layout_height="40dp"
+        android:layout_gravity="center_horizontal"
+        android:background="@drawable/drag_handle_bg" />
+
     <!-- Header -->
     <LinearLayout
         android:layout_width="match_parent"