feat(post-form): reverse-geocode City/Country + drop hero-image field

Get Location now reverse-geocodes the captured coordinates into City +
Country via BigDataCloud's free client endpoint, filling only blank fields
(never clobbering a manual entry) and appending the resolved place to the
location status. Best-effort — a failure leaves the coordinates intact.

Removes the redundant hero_image field: journal entries render their hero
from the first uploaded photo (entry-journal uses entry.media.images|first),
so an explicit hero filename served no purpose. Stories still use hero_image
but are not posted through this form.

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

pages/02.post/post-form.md

@@ -129,15 +129,11 @@ form:
                 'car': '🚗 Car'
                 'plane': '✈️ Plane'
 
-        # Advanced fields — collapsed behind "More options" (see U5)
+        # Advanced fields — collapsed behind "More options" (see U5).
-        -
+        # No hero_image field: journal entries render their hero from the first
-            name: hero_image
+        # uploaded photo (entry-journal.html.twig uses entry.media.images|first),
-            label: Hero Image Filename
+        # so an explicit hero filename was redundant. Stories still use hero_image
-            type: text
+        # but they aren't posted through this form.
-            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

themes/intotheeast/js/src/post-form.js

@@ -290,8 +290,8 @@ function field(name) {
 }
 
 /* ── "More options" disclosure (U5, KTD5) ─────────────────────
- * The blueprint renders the advanced trio (hero_image/force_connect/featured)
+ * The blueprint renders the advanced fields (force_connect/featured) flat;
- * flat; here we relocate their .form-field wrappers into a native <details> so
+ * here we relocate their .form-field wrappers into a native <details> so
  * they collapse by default with full keyboard/AT support. Auto-opens if any
  * advanced field already carries a value (edit / draft restore).
  */
@@ -370,6 +370,33 @@ function initGeo() {
     }
     syncWeatherEnabled();
 
+    // Reverse-geocode the captured coordinates into City + Country via
+    // BigDataCloud's free client endpoint (no API key, CORS-enabled). Only
+    // fills fields the traveller left blank — never clobbers a manual entry —
+    // and appends the resolved place to the location status. Best-effort: a
+    // failure leaves the coordinates (and the manual city/country fields) intact.
+    function reverseGeocode(lat, lng) {
+        var cityEl = field('location_city');
+        var countryEl = field('location_country');
+        // Nothing to fill if the traveller already typed both.
+        if ((!cityEl || cityEl.value.trim()) && (!countryEl || countryEl.value.trim())) return;
+
+        var url = 'https://api.bigdatacloud.net/data/reverse-geocode-client?latitude=' +
+            encodeURIComponent(lat) + '&longitude=' + encodeURIComponent(lng) + '&localityLanguage=en';
+        fetch(url).then(function (r) { return r.json(); }).then(function (data) {
+            // BigDataCloud's `city` is often empty in rural areas; `locality`
+            // is the more reliably-populated place name, so fall back to it.
+            var city = (data.city || data.locality || '').trim();
+            var country = (data.countryName || '').trim();
+            if (cityEl && !cityEl.value.trim() && city) cityEl.value = city;
+            if (countryEl && !countryEl.value.trim() && country) countryEl.value = country;
+            var place = [city, country].filter(Boolean).join(', ');
+            if (place) {
+                setStatus(locStatus, '✓ Location captured · ' + place, 'ok');
+            }
+        }).catch(function () { /* keep the coordinates-only status */ });
+    }
+
     if (locBtn) {
         locBtn.addEventListener('click', function () {
             if (!navigator.geolocation) {
@@ -390,6 +417,7 @@ function initGeo() {
                 locBtn.disabled = false;
                 setStatus(locStatus, '✓ Location captured · ' + lat + ', ' + lng, 'ok');
                 syncWeatherEnabled();
+                reverseGeocode(lat, lng); // fill City/Country in the background
             }, function (err) {
                 locBtn.classList.remove('is-loading');
                 locBtn.disabled = false;