fix: complete image_encoder→rad_dino rename (repair broken HEAD)

The file rename landed in 215ecd6 but the importer updates in
model/__init__.py, model/cxr_vlm.py, evaluation/{evaluate,inference}.py
and training/train.py were left uncommitted, so a clean checkout of HEAD
raised ImportError (from .image_encoder import …, file no longer exists).
Commit only those import-line fixes (6 lines) to make HEAD importable.

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

evaluation/evaluate.py

@@ -52,7 +52,7 @@ from tqdm import tqdm
 sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
 
 from model import CXRVisionLanguageModel
-from model.image_encoder import BioViLTEncoder
+from model.rad_dino import BioViLTEncoder
 from data import CXRInstructDataset, CXRDataCollator
 from data.prompt_templates import (
     build_findings_prompt,

evaluation/inference.py

@@ -67,7 +67,7 @@ from omegaconf import OmegaConf
 sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
 
 from model import CXRVisionLanguageModel
-from model.image_encoder import BioViLTEncoder
+from model.rad_dino import BioViLTEncoder
 from data.prompt_templates import (
     build_findings_prompt,
     build_impression_prompt,

model/__init__.py

@@ -1,4 +1,4 @@
 from .cxr_vlm            import CXRVisionLanguageModel
-from .image_encoder      import BioViLTEncoder
+from .rad_dino           import BioViLTEncoder
 from .projection         import MLPProjection
 from .chexpert_classifier import CheXpertClassifier

model/cxr_vlm.py

@@ -26,7 +26,7 @@ from omegaconf import DictConfig
 from transformers import AutoTokenizer, LlamaForCausalLM, BitsAndBytesConfig
 from peft import get_peft_model, LoraConfig, TaskType, PeftModel, prepare_model_for_kbit_training
 
-from .image_encoder import BioViLTEncoder
+from .rad_dino import BioViLTEncoder
 from .projection import MLPProjection
 from .chexpert_classifier import CheXpertClassifier
 
@@ -55,7 +55,7 @@ class CXRVisionLanguageModel(nn.Module):
 
         # ── 1. Image Encoder (rad_dino / biovilt / vit, frozen) ─────────────
         # `backend` defaults to "auto" → tries rad_dino → biovilt → vit and
-        # uses the first that loads (see model/image_encoder.py docstring).
+        # uses the first that loads (see model/rad_dino.py docstring).
         _enc_backend = getattr(model_cfg.image_encoder, "backend", "auto")
         self.image_encoder = BioViLTEncoder(
             frozen   = model_cfg.image_encoder.frozen,

training/train.py

@@ -40,7 +40,7 @@ from transformers import TrainingArguments, Trainer, TrainerCallback
 sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
 
 from model import CXRVisionLanguageModel
-from model.image_encoder import BioViLTEncoder
+from model.rad_dino import BioViLTEncoder
 from data import CXRInstructDataset, CXRDataCollator
 from utils.logger import setup_logger
 from utils.checkpoint import save_checkpoint, load_checkpoint