feat(post-form): expose all entry fields + weather picker (U2)

weather_desc hidden->select (emoji conditions mirroring entry.yaml),
weather_temp_c hidden->editable number, add transport_mode select and
the advanced trio (hero_image, force_connect, featured) tagged
advanced-field for U5's More options disclosure.

Refs R3, R4, R6, AE3.

pages/02.post/post-form.md

@@ -79,12 +79,78 @@ form:
             placeholder: 'e.g. Japan'
 
         -
-            name: weather_temp_c
+            name: weather_desc
-            type: hidden
+            label: Weather Condition
+            type: select
+            default: ''
+            options:
+                '': '— none —'
+                'Sunny': '☀️ Sunny'
+                'Partly cloudy': '⛅ Partly cloudy'
+                'Cloudy': '☁️ Cloudy'
+                'Foggy': '🌫️ Foggy'
+                'Drizzle': '🌦️ Drizzle'
+                'Rain': '🌧️ Rain'
+                'Snow': '❄️ Snow'
+                'Thunderstorm': '⛈️ Thunderstorm'
 
         -
-            name: weather_desc
+            name: weather_temp_c
-            type: hidden
+            label: 'Temperature (°C)'
+            type: number
+            placeholder: 'tap "Get Weather" or type it'
+            validate:
+                min: -60
+                max: 60
+
+        -
+            name: transport_mode
+            label: 'How I got here'
+            type: select
+            default: ''
+            options:
+                '': '— not specified —'
+                'walking': '🚶 Walking'
+                'bicycle': '🚲 Bicycle'
+                'bus': '🚌 Bus'
+                'train': '🚆 Train'
+                'car': '🚗 Car'
+                'plane': '✈️ Plane'
+
+        # Advanced fields — collapsed behind "More options" (see U5)
+        -
+            name: hero_image
+            label: Hero Image Filename
+            type: text
+            classes: advanced-field
+            placeholder: 'photo.jpg'
+            help: 'Filename of the hero/header image. Leave blank to use the first uploaded photo.'
+
+        -
+            name: force_connect
+            label: Force connector line
+            type: toggle
+            classes: advanced-field
+            highlight: 0
+            default: 0
+            options:
+                1: 'Yes'
+                0: 'No'
+            validate:
+                type: bool
+
+        -
+            name: featured
+            label: Featured highlight
+            type: toggle
+            classes: advanced-field
+            highlight: 0
+            default: 0
+            options:
+                1: 'Yes'
+                0: 'No'
+            validate:
+                type: bool
 
     novalidate: true