refactor(model-type): complete phase 5 cleanup by removing deprecated model_type field

- Remove backward compatibility code for `model_type` in `ModelScanner._build_cache_entry()`
- Update `CheckpointScanner` to only handle `sub_type` in `adjust_metadata()` and `adjust_cached_entry()`
- Delete deprecated aliases `resolve_civitai_model_type` and `normalize_civitai_model_type` from `model_query.py`
- Update frontend components (`RecipeModal.js`, `ModelCard.js`, etc.) to use `sub_type` instead of `model_type`
- Update API response format to return only `sub_type`, removing `model_type` from service responses
- Revise technical documentation to mark Phase 5 as completed and remove outdated TODO items

All cleanup tasks for the model type refactoring are now complete, ensuring consistent use of `sub_type` across the codebase.

static/js/components/shared/ModelCard.js

@@ -176,7 +176,7 @@ function handleSendToWorkflow(card, replaceMode, modelType) {
             return;
         }
 
-        const subtype = (card.dataset.model_type || 'checkpoint').toLowerCase();
+        const subtype = (card.dataset.sub_type || 'checkpoint').toLowerCase();
         const isDiffusionModel = subtype === 'diffusion_model';
         const widgetName = isDiffusionModel ? 'unet_name' : 'ckpt_name';
         const actionTypeText = translate(
@@ -453,9 +453,9 @@ export function createModelCard(model, modelType) {
         card.dataset.usage_tips = model.usage_tips;
     }
 
-    // checkpoint specific data
-    if (modelType === MODEL_TYPES.CHECKPOINT) {
-        card.dataset.model_type = model.model_type; // checkpoint or diffusion_model
+    // Set sub_type for all model types (lora/locon/dora, checkpoint/diffusion_model, embedding)
+    if (model.sub_type) {
+        card.dataset.sub_type = model.sub_type;
     }
 
     // Store metadata if available