fix(example-images): support importing for Other models and pending hashes

Two gaps kept 'import example images' from working on the Other page:

- import_images/delete_custom_image/set_example_image_nsfw_level only
  searched the lora/checkpoint/embedding scanners, so Other-category
  models were never found ('Model with hash ... not found in cache').
  All three now go through a shared scanner list that includes the
  Other scanner.
- Other models (and fresh checkpoints) carry hash_status=pending with
  an empty sha256, so the frontend sent an empty model_hash and the
  import was rejected with 'Missing model_hash parameter'. The modal
  now also sends the model's file path, and the import use case
  resolves the hash on demand via the scanner's lazy-hash calculation.
  The resolved hash is returned to the UI and persisted on the
  showcase element so follow-up operations target the same
  hash-keyed folder.

tests/services/test_use_cases.py

@@ -146,6 +146,8 @@ class StubExampleImagesProcessor(ExampleImagesProcessor):
         self.calls: List[Dict[str, Any]] = []
         self.error: Optional[str] = None
         self.response: Dict[str, Any] = {"success": True}
+        self.resolved_hash: Optional[str] = None
+        self.resolve_calls: List[str] = []
 
     async def import_images(self, model_hash: str, files: List[str]) -> Dict[str, Any]:  # pyright: ignore[reportIncompatibleMethodOverride]
         self.calls.append({"model_hash": model_hash, "files": files})
@@ -155,6 +157,10 @@ class StubExampleImagesProcessor(ExampleImagesProcessor):
             raise ExampleImagesImportError("boom")
         return self.response
 
+    async def resolve_hash_for_file_path(self, file_path: str) -> str:
+        self.resolve_calls.append(file_path)
+        return self.resolved_hash or ""
+
 
 async def test_auto_organize_use_case_executes_with_lock() -> None:
     file_service = StubFileService()
@@ -506,6 +512,34 @@ async def test_import_example_images_use_case_propagates_generic_error() -> None
         await use_case.execute(request)  # pyright: ignore[reportArgumentType]
 
 
+async def test_import_example_images_use_case_resolves_hash_from_model_path() -> None:
+    """Models with a deferred hash (checkpoints, Other) send model_path
+    instead of model_hash; the use case must resolve the hash on demand."""
+    processor = StubExampleImagesProcessor()
+    processor.resolved_hash = "f" * 64
+    use_case = ImportExampleImagesUseCase(processor=processor)
+
+    request = DummyJsonRequest(
+        {"model_path": "/models/vae/x.safetensors", "file_paths": ["/tmp/file"]}
+    )
+    result = await use_case.execute(request)  # pyright: ignore[reportArgumentType]
+
+    assert processor.resolve_calls == ["/models/vae/x.safetensors"]
+    assert processor.calls == [{"model_hash": "f" * 64, "files": ["/tmp/file"]}]
+    assert result == {"success": True}
+
+
+async def test_import_example_images_use_case_rejects_unresolvable_model_path() -> None:
+    processor = StubExampleImagesProcessor()
+    use_case = ImportExampleImagesUseCase(processor=processor)
+    request = DummyJsonRequest(
+        {"model_path": "/models/unknown.safetensors", "file_paths": []}
+    )
+
+    with pytest.raises(ImportExampleImagesValidationError):
+        await use_case.execute(request)  # pyright: ignore[reportArgumentType]
+
+
 class StubLifecycleService:
     def __init__(self, scanner: Optional[MockScanner] = None) -> None:
         self.renames: List[Dict[str, str]] = []