feat: add Image provider support with Trivy-based container scanning

- Add Image provider SDK with registry adapters (Docker Hub, OCI)
- Integrate Image scan path in Scan class alongside IaC provider
- Add CheckReportImage model and Finding output block for image results
- Add IMAGE enum, UID validation, and migration to API models
- Skip compliance and attack surface tasks for Image/IaC providers
- Bump Trivy to v0.69.1 and allow hyphenated CheckIDs for image provider

api/src/backend/api/migrations/0076_image_provider.py

@@ -0,0 +1,37 @@
+from django.db import migrations
+
+import api.db_utils
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("api", "0075_cloudflare_provider"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="provider",
+            name="provider",
+            field=api.db_utils.ProviderEnumField(
+                choices=[
+                    ("aws", "AWS"),
+                    ("azure", "Azure"),
+                    ("gcp", "GCP"),
+                    ("kubernetes", "Kubernetes"),
+                    ("m365", "M365"),
+                    ("github", "GitHub"),
+                    ("mongodbatlas", "MongoDB Atlas"),
+                    ("iac", "IaC"),
+                    ("oraclecloud", "Oracle Cloud Infrastructure"),
+                    ("alibabacloud", "Alibaba Cloud"),
+                    ("cloudflare", "Cloudflare"),
+                    ("image", "Image"),
+                ],
+                default="aws",
+            ),
+        ),
+        migrations.RunSQL(
+            "ALTER TYPE provider ADD VALUE IF NOT EXISTS 'image';",
+            reverse_sql=migrations.RunSQL.noop,
+        ),
+    ]