feat: fix travel placement bug, add theme-based alternate icons, fix animated background crash

- Fix repeat-city travel placement: use stop indices instead of global city name
  matching so Follow Team trips with repeat cities show travel correctly
- Add TravelPlacement helper and regression tests (7 tests)
- Add alternate app icons for each theme, auto-switch on theme change
- Fix index-out-of-range crash in AnimatedSportsBackground (19 configs, was iterating 20)
- Add marketing video configs, engine, and new video components
- Add docs and data exports

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

sportstime_export/sports_canonical.json

@@ -0,0 +1,72 @@
+[
+  {
+    "sport_id": "MLB",
+    "abbreviation": "MLB",
+    "display_name": "Major League Baseball",
+    "icon_name": "baseball.fill",
+    "color_hex": "#FF0000",
+    "season_start_month": 3,
+    "season_end_month": 10,
+    "is_active": true
+  },
+  {
+    "sport_id": "MLS",
+    "abbreviation": "MLS",
+    "display_name": "Major League Soccer",
+    "icon_name": "soccerball",
+    "color_hex": "#34C759",
+    "season_start_month": 2,
+    "season_end_month": 12,
+    "is_active": true
+  },
+  {
+    "sport_id": "NBA",
+    "abbreviation": "NBA",
+    "display_name": "National Basketball Association",
+    "icon_name": "basketball.fill",
+    "color_hex": "#FF8C00",
+    "season_start_month": 10,
+    "season_end_month": 6,
+    "is_active": true
+  },
+  {
+    "sport_id": "NFL",
+    "abbreviation": "NFL",
+    "display_name": "National Football League",
+    "icon_name": "football.fill",
+    "color_hex": "#8B4513",
+    "season_start_month": 9,
+    "season_end_month": 2,
+    "is_active": true
+  },
+  {
+    "sport_id": "NHL",
+    "abbreviation": "NHL",
+    "display_name": "National Hockey League",
+    "icon_name": "hockey.puck.fill",
+    "color_hex": "#007AFF",
+    "season_start_month": 10,
+    "season_end_month": 6,
+    "is_active": true
+  },
+  {
+    "sport_id": "NWSL",
+    "abbreviation": "NWSL",
+    "display_name": "National Women's Soccer League",
+    "icon_name": "soccerball",
+    "color_hex": "#5AC8FA",
+    "season_start_month": 3,
+    "season_end_month": 11,
+    "is_active": true
+  },
+  {
+    "sport_id": "WNBA",
+    "abbreviation": "WNBA",
+    "display_name": "Women's National Basketball Association",
+    "icon_name": "basketball.fill",
+    "color_hex": "#AF52DE",
+    "season_start_month": 5,
+    "season_end_month": 10,
+    "is_active": true
+  }
+]