Fix review comments: restore null=True, fix None url, re-add listeners import

- Restore null=True on companies.Company contact/email/url fields to avoid
  unintended schema change (noqa DJ001 since removal needs migration)
- Guard against None return from fix_image() in fix_success_story_images
- Re-add jobs.listeners import in JobsAppConfig.ready() for signal registration
- Prefix unused unpacked variables with underscore for RUF059

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

Author: JacobCoffee

companies/models.py

@@ -14,9 +14,9 @@ class Company(NameSlugModel):
     """A company that uses Python, displayed in the company directory."""
 
     about = MarkupField(blank=True, default_markup_type=DEFAULT_MARKUP_TYPE)
-    contact = models.CharField(blank=True, max_length=100)
-    email = models.EmailField(blank=True)
-    url = models.URLField("URL", blank=True)
+    contact = models.CharField(blank=True, null=True, max_length=100)  # noqa: DJ001
+    email = models.EmailField(blank=True, null=True)  # noqa: DJ001
+    url = models.URLField("URL", blank=True, null=True)  # noqa: DJ001
     logo = models.ImageField(upload_to="companies/logos/", blank=True, null=True)
 
     class Meta:

jobs/apps.py

@@ -11,3 +11,4 @@ class JobsAppConfig(AppConfig):
 
     def ready(self):
         """Perform app initialization on startup."""
+        import jobs.listeners  # noqa: F401

pages/management/commands/fix_success_story_images.py

@@ -70,6 +70,8 @@ def process_success_story(self, page):
 
         for path in image_paths:
             new_url = self.fix_image(path, page)
+            if not new_url:
+                continue
             content = page.content.raw
             new_content = content.replace(path, new_url)
             page.content = new_content