fix(config): respect --force for bare model key overwrite

--force was silently ignored for 'model' keys — the guard always
redirected to model.default even when the user explicitly asked to
replace the entire section. Now --force triggers a warning and
proceeds with the destructive overwrite for model too, matching
the non-model mapping --force behaviour.

hermes_cli/config.py

@@ -4866,14 +4866,21 @@ def set_config_value(key: str, value: str, force: bool = False):
         _existing = user_config.get(key)
         if isinstance(_existing, dict):
             if key == "model":
-                # Redirect bare-model shorthand to model.default while
-                # keeping every sibling mapping key intact.
-                key = "model.default"
-                print(
-                    f"✓ Redirecting bare 'model' to 'model.default' "
-                    f"(preserving {len(_existing)} existing model sub-key(s))"
-                )
-                # value was already coerced above; proceed to _set_nested
+                if force:
+                    # --force: allow destructive section overwrite.
+                    print(
+                        f"⚠ Replacing entire 'model' section with a scalar "
+                        f"(discarding {len(_existing)} existing sub-key(s))"
+                    )
+                else:
+                    # Redirect bare-model shorthand to model.default while
+                    # keeping every sibling mapping key intact.
+                    key = "model.default"
+                    print(
+                        f"✓ Redirecting bare 'model' to 'model.default' "
+                        f"(preserving {len(_existing)} existing model sub-key(s))"
+                    )
+                    # value was already coerced above; proceed to _set_nested
             elif not force:
                 _sub = [k for k in _existing if isinstance(k, str)]
                 print(

tests/hermes_cli/test_set_config_value.py

@@ -643,3 +643,17 @@ class TestMappingGuard:
         parsed = _yaml.safe_load(_read_config(_isolated_hermes_home))
         assert parsed["model"]["default"] == "claude-opus-4"
         assert parsed["model"]["provider"] == "openai-api"
+
+    def test_model_force_overwrites_entire_section(self, _isolated_hermes_home):
+        """hermes config set --force model <id> → overwrite entire section."""
+        self._write_config(_isolated_hermes_home, {
+            "model": {
+                "default": "gpt-4o",
+                "provider": "openai-api",
+                "context_length": 128_000,
+            }
+        })
+        set_config_value("model", "claude-opus-4", force=True)
+        import yaml as _yaml
+        parsed = _yaml.safe_load(_read_config(_isolated_hermes_home))
+        assert parsed["model"] == "claude-opus-4"