Add support for bookmark thumbnails (#721)

* Preview Image

* fix tests

* add test

* download preview image

* relative path

* gst

* details view

* fix tests

* Improve preview image styles

* Remove preview image URL from model

* Revert form changes

* update tests

* make it work in uwsgi

---------

Co-authored-by: Sascha Ißbrücker <sascha.issbruecker@gmail.com>

bookmarks/migrations/0034_bookmark_preview_image_file_and_more.py

@@ -0,0 +1,23 @@
+# Generated by Django 5.0.3 on 2024-05-07 07:27
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bookmarks", "0033_userprofile_default_mark_unread"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="bookmark",
+            name="preview_image_file",
+            field=models.CharField(blank=True, max_length=512, null=True),
+        ),
+        migrations.AddField(
+            model_name="userprofile",
+            name="enable_preview_images",
+            field=models.BooleanField(default=False),
+        ),
+    ]