fix(preprocess): initialize fresh DWH writers safely

harness/tht/cli/schema_cmd.py

@@ -72,8 +72,11 @@ def introspect_cmd(
     Se physical.yaml esiste già, esce subito (cache); usa --refresh per rigenerarlo.
     """
     cfg = _load_config_or_exit(config)
-    out = physical_path(cfg)
-    if out.exists() and not refresh:
+    dwh_root = cfg.paths.artifacts.parent / ".tht-dwh"
+    out = cfg.paths.artifacts / "mschema" / "physical.yaml"
+    if dwh_root.exists() or dwh_root.is_symlink():
+        out = physical_path(cfg)
+    if (dwh_root.exists() or dwh_root.is_symlink()) and out.exists() and not refresh:
         from datetime import UTC, datetime
 
         from tht.mschema.models import PhysicalSchema
@@ -94,18 +97,14 @@ def introspect_cmd(
             )
             return
     try:
-        from tht.jobs.dwh_pipeline import resolve_dwh_snapshot
+        from tht.cli.preprocess_cmd import run_dwh_from_config
+        from tht.mschema.models import PhysicalSchema
 
-        if resolve_dwh_snapshot(cfg).generation is None:
-            phys = refresh_catalog(cfg)
-        else:
-            from tht.cli.preprocess_cmd import run_dwh_from_config
-            from tht.mschema.models import PhysicalSchema
-
-            report = run_dwh_from_config(config, steps=("introspect",))
-            if report.status != "succeeded":
-                raise RuntimeError("DWH preprocessing failed")
-            phys = PhysicalSchema.from_yaml(physical_path(cfg))
+        report = run_dwh_from_config(config, steps=("introspect",))
+        if report.status != "succeeded":
+            raise RuntimeError("DWH preprocessing failed")
+        out = physical_path(cfg)
+        phys = PhysicalSchema.from_yaml(out)
     except Exception as e:
         typer.secho(f"ERRORE: {e}", fg=typer.colors.RED, err=True)
         raise typer.Exit(code=1)