content(trip): add taglines for all trips; refine Denmark tagline

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

pages/01.trips/central-asia-2023/trip.md

@@ -5,4 +5,5 @@ date: '2023-08-28'
 date_start: '2023-08-28'
 date_end: '2023-10-18'
 cover_image: ''
+tagline: 'Seven weeks overland across Central Asia — the Pamir Highway, plov, and endless steppe'
 ---

pages/01.trips/denmark-2026/trip.md

@@ -5,7 +5,7 @@ date: '2026-07-10'
 date_start: '2026-07-10'
 date_end: '2026-07-20'
 cover_image: bikepacking_denmark.jpeg
-tagline: '10 days along the West Coast to the top of Denmark'
+tagline: '560 km up Denmark''s wild North Sea coast to where two seas meet'
 published: false
 autoconnect: intelligent_gpx
 ---

pages/01.trips/italy-2025/trip.md

@@ -5,4 +5,5 @@ date: '2025-09-01'
 date_start: '2025-09-01'
 date_end: '2025-09-08'
 cover_image: ''
+tagline: '600 km of Tuscan gravel — hill towns, aperitivi, and relentless climbing'
 ---

pages/01.trips/slovenia-2024/trip.md

@@ -5,4 +5,5 @@ date: '2024-05-28'
 date_start: '2024-05-28'
 date_end: '2024-05-28'
 cover_image: ''
+tagline: 'Gelato and Venetian walls on Slovenia''s slip of Adriatic coast'
 ---

pages/01.trips/us-canada-mex-2024/trip.md

@@ -5,4 +5,5 @@ date: '2024-07-21'
 date_start: '2024-07-21'
 date_end: '2024-08-07'
 cover_image: ''
+tagline: 'Three weeks across North America — Highway 1, craft beer, Niagara, and Mexico City'
 ---