fix(storage): harden portable path diagnostics

harness/tht/cli/doctor_cmd.py

@@ -6,6 +6,7 @@ from pathlib import Path
 from typing import Any
 
 import typer
+import yaml
 
 from tht.cli.config_cmd import CONFIG_OPT
 from tht.config import ConfigError, load_config
@@ -17,7 +18,14 @@ def _emit(payload: dict[str, Any], as_json: bool) -> None:
         typer.echo(json.dumps(payload, sort_keys=True))
         return
     for component, result in payload["components"].items():
-        typer.echo(f"{component}: {result['status']}")
+        detail = ""
+        if result["status"] == "error":
+            detail = f" - {result['message']}"
+        elif component == "data_root" and result["status"] == "warning":
+            detail = " - set THT_DATA_ROOT to enable portable storage"
+        elif component == "workspace_paths" and result["status"] == "warning":
+            detail = " - absolute legacy roots: " + ", ".join(result["legacy_absolute"])
+        typer.echo(f"{component}: {result['status']}{detail}")
 
 
 def doctor(
@@ -32,11 +40,11 @@ def doctor(
     }
     try:
         cfg = load_config(config)
-    except ConfigError as exc:
-        path_error = "outside workspace root" in str(exc)
+    except (ConfigError, yaml.YAMLError, OSError) as exc:
+        path_error = isinstance(exc, ConfigError) and "outside workspace" in str(exc)
         target = "workspace_paths" if path_error else "config"
         # Validation errors can contain Pydantic input excerpts, including credentials.
-        message = str(exc) if path_error else "configuration is invalid"
+        message = str(exc) if path_error else "configuration is invalid or unreadable"
         components[target] = {"status": "error", "message": message}
         payload = {"ok": False, "components": components}
         _emit(payload, as_json)