fix(import): discover LoRA + checkpoint from modelVersionIds when API meta is null

When CivitAI image API returns meta=null and modelVersionIds at root
level, the import flow now:

- Injects modelVersionIds + browsingLevel into a minimal metadata dict
  so the parser can discover LoRAs and checkpoints (both import-from-url
  and analyze-image paths)
- Adds checkpoint dedup + fallback in the parser's modelVersionIds
  handler to avoid duplicate API calls
- Runs EXIF extraction unconditionally in analyze-image path, then
  merges with API metadata (fixes gen params loss)
- Propagates preview_nsfw_level through all three import paths:
  import-from-url, analyze-image (UI Import), and batch-import,
  plus the frontend save flow

py/recipes/parsers/civitai_image.py

@@ -526,6 +526,13 @@ class CivitaiApiMetadataParser(RecipeMetadataParser):
                     if version_id_str in added_loras:
                         continue
 
+                    # Skip if this version ID is already the recipe's checkpoint
+                    # (resolved earlier from embedded resources/Model hash,
+                    # avoiding a duplicate CivitAI API call).
+                    existing_model = result.get("model")
+                    if existing_model and str(existing_model.get("id")) == version_id_str:
+                        continue
+
                     # Initialize lora entry with version ID
                     lora_entry = {
                         "id": version_id,
@@ -559,7 +566,37 @@ class CivitaiApiMetadataParser(RecipeMetadataParser):
                             )
 
                             if populated_entry is None:
-                                continue  # Skip invalid LoRA types
+                                # Not a LoRA — try as checkpoint (only if we
+                                # don't already have one).  Reuses the same
+                                # civitai_info from the API call above so no
+                                # extra query is made.
+                                if result["model"] is None:
+                                    checkpoint_entry = {
+                                        "id": version_id,
+                                        "modelId": 0,
+                                        "name": "Unknown Model",
+                                        "version": "",
+                                        "type": "checkpoint",
+                                        "existsLocally": False,
+                                        "localPath": None,
+                                        "file_name": "",
+                                        "hash": "",
+                                        "thumbnailUrl": (
+                                            "/loras_static/images/no-preview.png"
+                                        ),
+                                        "baseModel": "",
+                                        "size": 0,
+                                        "downloadUrl": "",
+                                        "isDeleted": False,
+                                    }
+                                    cp_populated = await (
+                                        self.populate_checkpoint_from_civitai(
+                                            checkpoint_entry, civitai_info
+                                        )
+                                    )
+                                    if cp_populated.get("id"):
+                                        result["model"] = cp_populated
+                                continue  # Not a LoRA, don't add to loras
 
                             lora_entry = populated_entry
                         except Exception as e: