fix(story): restore datetime type, use date-only format; strip times from demo stories

Reverts text→datetime change. Uses format:'Y-m-d' (date-only) so the
datepicker omits the time component. Strips HH:MM from all Italy demo
story dates for consistency with the new date-only format.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Vgmzx8VTTTmCskSpQtsLTr

docs/demo/trips/italy-2025/04.stories/01.val-dorcia-dawn/story.md

@@ -1,6 +1,6 @@
 ---
 title: The Val d'Orcia at Dawn
-date: '2025-09-05 10:00'
+date: '2025-09-05'
 location_name: Val d'Orcia
 location_country: Italy
 lat: 43.078

docs/demo/trips/italy-2025/04.stories/02.long-climb-montalcino/story.md

@@ -1,6 +1,6 @@
 ---
 title: The Long Climb to Montalcino
-date: '2025-09-06 20:00'
+date: '2025-09-06'
 location_name: Montalcino
 location_country: Italy
 lat: 43.058

docs/demo/trips/italy-2025/04.stories/03.one-evening-siena/story.md

@@ -1,6 +1,6 @@
 ---
 title: One Evening in Siena
-date: '2025-09-05 22:00'
+date: '2025-09-05'
 location_name: Siena
 location_country: Italy
 lat: 43.318

pages/01.trips/italy-2025/04.stories/01.val-dorcia-dawn/story.md

@@ -0,0 +1,28 @@
+---
+title: The Val d'Orcia at Dawn
+date: '2025-09-05'
+location_name: Val d'Orcia
+location_country: Italy
+lat: 43.078
+lng: 11.676
+hero_image: hero.jpg
+hero_alt: Cypress-lined dirt road at first light, Tuscany
+published: true
+---
+We left camp before the heat arrived. At six in the morning the Val d'Orcia belongs entirely to the light — long shadows, pale gold, not a car on the white roads. The kind of silence that has texture.
+
+[snap-gallery images="hero.jpg,photo.jpg" captions="First light on the valley floor,The hills fold endlessly east" alts="Wide valley at dawn with golden light,Rolling green hills under morning sky" /]
+
+We stopped twice before nine. Once for a puncture, once because the view demanded it.
+
+[chapter-break image="hero.jpg" title="The Hour Before Heat" alt="Hazy hillside shimmering in early morning warmth" /]
+
+By ten the temperature had shifted. The colours changed too — softer, more diffuse, the sky turning white at the edges. We dropped into the lower valley and the road surface changed from gravel to packed earth, then back again.
+
+[snap-gallery images="photo.jpg,hero.jpg" captions="The texture of Tuscan gravel — coarser than it looks,The road ahead disappears into the heat" alts="Close-up of pale gravel surface,Road vanishing into bright haze" /]
+
+[pull-quote]
+The best hours of a cycling day are the ones nobody sees. Four in the morning to ten. Then it belongs to the sun.
+[/pull-quote]
+
+We made Pienza by noon. It was already thirty degrees and the ice cream queue was six deep.

pages/01.trips/italy-2025/04.stories/02.long-climb-montalcino/story.md

@@ -1,6 +1,6 @@
 ---
 title: 'The Long Climb to Montalcino'
-date: '2025-09-06 20:00'
+date: '2025-09-06'
 location_name: Montalcino
 location_country: Italy
 lat: 43.058

pages/01.trips/italy-2025/04.stories/03.one-evening-siena/story.md

@@ -0,0 +1,32 @@
+---
+title: One Evening in Siena
+date: '2025-09-05'
+location_name: Siena
+location_country: Italy
+lat: 43.318
+lng: 11.330
+hero_image: hero.jpg
+hero_alt: The Piazza del Campo at dusk, terracotta rooftops fading to blue
+published: true
+---
+[pull-quote]
+Siena is not a city that tries to impress you. It has been here for a thousand years and intends to be here for a thousand more. You fit around it.
+[/pull-quote]
+
+We rolled in at half past six, legs finished, panniers heavier than they started. The Campo appeared without warning at the end of a narrow street and we both stopped pedalling at exactly the same moment.
+
+[scrolly-section image="hero.jpg" alt="Piazza del Campo seen from the upper rim, sloping shell-shaped square"]
+The square fills from the edges inward as evening comes. First the locals — people who have been here before and know which bench faces west. Then the tourists, then the pigeons, then the shadows.
+
+---
+
+A busker with a cello at the top of the slope. A couple arguing quietly in a language I couldn't place. Three children running in a circle for reasons nobody questioned. The ordinary business of a city at the end of a summer day.
+[/scrolly-section]
+
+[snap-gallery images="hero.jpg,photo.jpg" captions="The Campo at the moment the light goes warm,A doorway on Via di Città — every doorway in Siena looks like this" alts="Wide shot of Campo at golden hour,Ornate stone doorway with iron lantern" /]
+
+We found a place to eat down three flights of stairs in a basement that appeared to have no ventilation and no menu. It was perfect. The relief of sitting down after eight hours on a bike is a specific physical sensation that is difficult to describe to anyone who has not experienced it.
+
+[pull-quote image="photo.jpg" alt="Sunset view over Siena rooftops from high vantage point"]
+Cycling makes you earn every place you arrive at. Siena earned.
+[/pull-quote]

themes/intotheeast/blueprints/story.yaml

@@ -18,18 +18,17 @@ form:
                 required: true
 
             header.date:
-              type: text
+              type: datetime
               label: Start Date
-              placeholder: '2025-09-06 20:00'
+              format: 'Y-m-d'
-              help: 'Format: YYYY-MM-DD HH:MM'
               validate:
                 required: true
 
             header.end_date:
-              type: text
+              type: datetime
               label: End Date
-              placeholder: '2025-09-12'
+              format: 'Y-m-d'
-              help: 'Format: YYYY-MM-DD — leave blank for a single-day story'
+              help: 'Optional — leave blank for a single-day story'
 
             header.hero_image:
               type: text