refactor(vault): trim the malformed-state coverage and drop the load_config shape guard

load_config() always returns a dict, so the isinstance re-init was
defense-in-depth. Coverage folded to one invariant per bug and surface:
every VaultStore reader raises VaultError on a corrupt file, `hermes
vault` prints a clean error line, and both the CLI sources toggle and
the TUI vault.source.set RPC persist the opt-out over a scalar section.

hermes_cli/vault.py

@@ -152,8 +152,6 @@ def _cmd_sources(args) -> None:
             c.print(f"[red]Unknown password manager {name!r}[/] (expected one of {', '.join(classes)})")
             return
         cfg = load_config()
-        if not isinstance(cfg, dict):
-            cfg = {}
         section = _ensure_dict(_ensure_dict(cfg, "vault"), name)
         if args.enable:
             section.pop("enabled", None)  # detected managers are on by default; drop the opt-out

tests/agent/test_vault_store.py

@@ -24,27 +24,6 @@ def _store(tmp_path) -> VaultStore:
     return store
 
 
-def test_malformed_json_vault_file_raises_vault_error(tmp_path):
-    store = _store(tmp_path)
-    _corrupt(store, b"{not json")
-    with pytest.raises(VaultError, match="corrupted"):
-        store.list_items()
-
-
-def test_non_dict_json_vault_file_raises_vault_error(tmp_path):
-    store = _store(tmp_path)
-    _corrupt(store, b"[1, 2]")
-    with pytest.raises(VaultError, match="corrupted"):
-        store.list_items()
-
-
-def test_non_utf8_vault_file_raises_vault_error(tmp_path):
-    store = _store(tmp_path)
-    _corrupt(store, b"\xff\xfe\x00binary")
-    with pytest.raises(VaultError, match="corrupted"):
-        store.list_items()
-
-
 @pytest.mark.parametrize(
     "op",
     ["list_items", "get_meta", "remove_item", "resolve_secret", "add_item"],

tests/hermes_cli/test_vault_sources_shape.py

@@ -8,7 +8,7 @@ from types import SimpleNamespace
 import yaml
 
 from agent.vault_store import VaultStore
-from hermes_cli.vault import _cmd_rm, _cmd_sources, vault_command
+from hermes_cli.vault import _cmd_sources, vault_command
 
 
 def _corrupt_vault(home):
@@ -47,16 +47,3 @@ def test_vault_command_surfaces_corrupt_store_as_clean_error(tmp_path, monkeypat
     out = capsys.readouterr().out
     assert "Error" in out
     assert "corrupted" in out
-
-
-def test_vault_rm_surfaces_corrupt_store_as_clean_error(tmp_path, monkeypatch, capsys):
-    home = tmp_path / ".hermes"
-    home.mkdir()
-    monkeypatch.setenv("HERMES_HOME", str(home))
-    _corrupt_vault(home)
-
-    vault_command(SimpleNamespace(_vault_handler=_cmd_rm, handle="vault_x"))
-
-    out = capsys.readouterr().out
-    assert "Error" in out
-    assert "corrupted" in out

tests/tui_gateway/test_vault_methods.py

@@ -156,53 +156,6 @@ def test_source_set_tolerates_scalar_vault_section(home, monkeypatch):
     assert rows["bitwarden"]["enabled"] is False
 
 
-def test_source_set_tolerates_scalar_named_section(home, monkeypatch):
-    """``vault: {bitwarden: true}`` must not crash either: the named section is
-    coerced before ``enabled`` is written."""
-    monkeypatch.setattr(
-        "agent.vault_backends.base.is_installed", lambda name: name == "bitwarden"
-    )
-    (home / "config.yaml").write_text("vault:\n  bitwarden: true\n")
-    _result(
-        srv._methods["vault.source.set"](83, {"name": "bitwarden", "enabled": False})
-    )
-    rows = _sources_rows(home)
-    assert rows["bitwarden"]["enabled"] is False
-
-
-def test_source_set_enable_tolerates_scalar_vault_section(home, monkeypatch):
-    """The enable arm (``section.pop``) must also survive a scalar ``vault:``
-    section: coercion happens before either write shape."""
-    monkeypatch.setattr(
-        "agent.vault_backends.base.is_installed", lambda name: name == "bitwarden"
-    )
-    (home / "config.yaml").write_text("vault: true\n")
-    _result(
-        srv._methods["vault.source.set"](84, {"name": "bitwarden", "enabled": True})
-    )
-    rows = _sources_rows(home)
-    assert rows["bitwarden"]["enabled"] is True
-
-
-def test_vault_list_reports_corrupt_store_cleanly(home):
-    """A decryptable-but-malformed vault file degrades to the 5095 envelope
-    carrying the VaultError text, never a traceback."""
-    from agent.vault_store import VaultStore
-
-    store = VaultStore(home / "vault")
-    store.add_item(
-        "login",
-        "site",
-        {"identifier_type": "email", "identifier": "u", "password": "p"},
-        origin="https://x.example",
-    )
-    store._vault_path.write_bytes(store._fernet().encrypt(b"{not json"))
-
-    err = _error(srv._methods["vault.list"](95, {}))
-    assert err["code"] == 5095
-    assert "corrupted" in err["message"]
-
-
 def test_remove_is_idempotent(home):
     item_id = _result(srv._methods["vault.add"](1, dict(_LOGIN_PARAMS)))["id"]
     assert _result(srv._methods["vault.remove"](2, {"id": item_id}))["removed"] is True

tui_gateway/methods_vault.py

@@ -88,8 +88,6 @@ def _(rid, params: dict) -> dict:
         return _err(rid, 5095, f"unknown vault source: {name}")
     enabled = bool(params.get("enabled"))
     cfg = load_config()
-    if not isinstance(cfg, dict):
-        cfg = {}
     section = _ensure_dict(_ensure_dict(cfg, "vault"), name)
     if enabled:
         section.pop("enabled", None)  # detected managers are on by default; this removes the opt-out