feat: show Pl@ntNet reference images on confirm screen + save as thumbnail

Extract image_url from Pl@ntNet API response (medium size). Show thumbnail
in each match card on identify_confirm. On plant creation, download the
selected match's reference image and save as PlantPhoto thumbnail. Scan
photos saved as gallery photos (non-thumbnail) with fallback to first scan
photo as thumbnail when Pl@ntNet has no image.

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

plants/services/plantnet.py

@@ -62,6 +62,7 @@ def identify(images):
                 'gbif_id': (r.get('gbif') or {}).get('id'),
                 'family': r['species'].get('family', {}).get('scientificNameWithoutAuthor', ''),
                 'genus': r['species'].get('genus', {}).get('scientificNameWithoutAuthor', ''),
+                'image_url': ((r.get('images') or [{}])[0].get('url') or {}).get('m'),
             }
             for r in results[:5]
         ]

plants/templates/plants/identify_confirm.html

@@ -20,6 +20,12 @@
              data-idx="{{ forloop.counter0 }}"
              data-name="{{ m.scientific_name }}"
              onclick="selectMatch(this)">
+            {% if m.image_url %}
+            <img src="{{ m.image_url }}" alt="{{ m.scientific_name }}"
+                 style="width:64px;height:64px;object-fit:cover;border-radius:8px;flex-shrink:0;">
+            {% else %}
+            <div style="width:64px;height:64px;background:#e9ecef;border-radius:8px;flex-shrink:0;"></div>
+            {% endif %}
             <div class="flex-grow-1">
                 <div class="fw-bold">{{ m.scientific_name }}</div>
                 {% if m.common_names %}

plants/views/identify.py

@@ -1,6 +1,7 @@
 import logging
 import os
 import uuid
+import requests
 from django.shortcuts import render, redirect
 from django.core.files.base import ContentFile
 from django.core.files.storage import default_storage
@@ -172,6 +173,19 @@ def identify_fields(request):
         plant = Plant.objects.create(name=name, species=species)
 
         try:
+            # Download Pl@ntNet reference image as thumbnail
+            plantnet_img_url = selected.get('image_url')
+            if plantnet_img_url:
+                try:
+                    r = requests.get(plantnet_img_url, timeout=10)
+                    r.raise_for_status()
+                    thumb_filename = f'plantnet_{uuid.uuid4().hex}.jpg'
+                    thumb = PlantPhoto(plant=plant, is_thumbnail=True)
+                    thumb.image.save(thumb_filename, ContentFile(r.content), save=True)
+                except Exception:
+                    logger.exception('identify_fields: failed to download Pl@ntNet image')
+
+            # Save uploaded scan photos; only first becomes thumbnail if no Pl@ntNet image
             image_paths = request.session.get('identify_image_paths', [])
             for i, p in enumerate(image_paths):
                 if not default_storage.exists(p['path']):
@@ -180,7 +194,7 @@ def identify_fields(request):
                     with default_storage.open(p['path'], 'rb') as fh:
                         data = fh.read()
                     filename = os.path.basename(p['path'])
-                    photo = PlantPhoto(plant=plant, is_thumbnail=(i == 0))
+                    photo = PlantPhoto(plant=plant, is_thumbnail=(i == 0 and not plantnet_img_url))
                     photo.image.save(filename, ContentFile(data), save=True)
                 except Exception:
                     logger.exception('identify_fields: failed to save photo %s', p['path'])