feat: add descriptive model naming and inline rename

- Auto-generate model names: {arch}-{labelType}-{epochs}ep-{classNames}-{YYYYMMDD}
- Add PATCH /api/models/{id}/rename endpoint
- Inline rename UI on Models & Training page
- Download filename uses model name instead of v{N}
- DB migration: add name column to model_versions
- Update all docs to reflect new naming convention

backend/api/live_count.py

@@ -46,7 +46,7 @@ def available_models(project_id: int) -> dict:
     for version in training.listing(project_id):
         if version.get("weights_path") and os.path.isfile(version["weights_path"]):
             out.append({
-                "label": f"v{version['version']}",
+                "label": version.get("name") or f"v{version['version']}",
                 "path": version["weights_path"],
                 "version_id": version["id"],
             })