UI-05: rebuild Record screen as the Map HUD (design north star)

Replaces the scrolling stats-card layout with the full-bleed Map HUD:
UI-04's draggable/resizable HUD widgets float over UI-01's shared
background map (full opacity on this tab), and the old Pause/Stop/Resume/
Discard buttons become full-bleed, icon-only segments matching the
mockup's tertiary-container/error-container colors exactly. The idle
state keeps its prior compact layout deliberately -- HUD widgets only
appear once a ride exists, preserving the existing "a resting screen
must not look like a ride going nowhere" guarantee rather than
reinterpreting it.

State-machine logic (ticker, wakelock, speed subscription, error
handling) is untouched; every pre-existing record-screen test passed
unchanged against the rebuilt screen. Added tests that actually tap
Start/Pause/Stop and verify engine state changes, confirm HUD widgets
render over the map rather than replacing it, and verify the
mounted-mode speed digit's real contrast ratio against GlassPanel's
translucent surface specifically (the ticket's own named risk).

Corrects a UI-04 mistake found while implementing this ticket: the HUD's
default four metrics were ordered Speed/Distance/Elapsed/Max Speed, a
guess made before reading the actual Map HUD mockup HTML closely. The
real fixed row is Speed/Avg Speed/Dist/Time -- reordered HudMetric to
match and updated every test that asserted the old order.

Adds PulsingLocationMarker (UI-03) to RideMap's live usage via a new
showLocationMarker flag, and explicit tertiaryContainer/errorContainer
tokens to ripprColors so the control bar matches the design system's
literal values rather than an auto-derived tonal palette.

Verified end-to-end on a real emulator: Start, Pause, Resume, and Stop
all correctly drive the trip state machine with the full live map behind
everything. A lengthy false alarm during this verification (taps
appearing to do nothing) turned out to be a screenshot-scale
mis-measurement on the verification side, not an app defect -- resolved
by sampling pixel colors directly from the raw screenshot to find the
control bar's true on-screen position.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012Xki7YAcc2TiN2PRZJ2tXr

lib/src/ui/theme.dart

@@ -45,6 +45,12 @@ const ripprColors = ColorScheme.dark(
   secondary: Color(0xFFAEC7F6),
   tertiary: _referenceOrange,
   onTertiary: Color(0xFF532200),
+  // UI-05: explicit rather than left to `ColorScheme.dark`'s own M3 tonal-palette
+  // derivation -- the Map HUD's Pause/Stop control bar needs to match the design
+  // system's literal `tertiary-container`/`error-container` tokens exactly, not
+  // whatever a generated tonal palette happens to compute from `tertiary`/`error` alone.
+  tertiaryContainer: Color(0xFFE3711F),
+  onTertiaryContainer: Color(0xFF481D00),
   surface: _surfaceMid,
   onSurface: _ink,
   surfaceContainerHighest: Color(0xFF353534),
@@ -57,6 +63,8 @@ const ripprColors = ColorScheme.dark(
   outlineVariant: Color(0xFF414753),
   error: _danger,
   onError: Color(0xFF690005),
+  errorContainer: Color(0xFF93000A),
+  onErrorContainer: Color(0xFFFFDAD6),
 );
 
 /// The near-black ground the whole app sits on.