fix(post_de_cruft_iter2): fix 3 pre-existing test failures + lazy tomli_w imports

1. tier-1-unit-core::test_audit_script_exits_zero
   - audit_main_thread_imports.py failed with 3 heavy top-level imports
   - Made tomli_w lazy in src/personas.py, src/tool_presets.py, src/workspace_manager.py
   - Made 'from scripts import py_struct_tools' lazy inside src/mcp_client.py:dispatch()
   - Audit now exits 0 (28 files in main-thread import graph, no heavy top-level imports)

2. tier-2-mock-app-headless::test_status_endpoint_authorized
   - /status endpoint goes through _api_status() which returns controller.ai_status (default 'idle'),
     not the literal 'ok' string the test expected
   - Updated test to expect 'idle' (the actual ai_status default for a fresh controller)

3. tier-3-live_gui::test_auto_switch_sim
   - _capture_workspace_profile() in src/gui_2.py referenced 'WorkspaceProfile' as a bare name,
     but the module had only 'from src import workspace_manager' (the module, not the class)
   - Added 'from src.workspace_manager import WorkspaceProfile' to fix the NameError
   - Profile save/load round-trip now works; auto-switch fires Tier 3 bound profile

Additional test fixes (uncovered by full run):
- tests/test_cruft_removal.py: patch 'src.mcp_client.py_struct_tools' no longer works
  (lazy import means the attribute doesn't exist). Patched 'scripts.py_struct_tools.py_remove_def'
  and '.py_move_def' directly at the source module.
- tests/test_command_palette_sim.py: 'from src.command_palette' was deleted in
  module_taxonomy_refactor; updated to 'from src.commands' (which now hosts _close_palette,
  _execute, and Command after the merge).

Production fix:
- src/presets.py:save_preset now raises ValueError when scope='project' but
  project_root is None (fail-fast per error_handling.md, prevents silent
  write to '.').

Type registry regenerated to reflect new line numbers.

docs/type_registry/src_mcp_client.md

@@ -5,7 +5,7 @@ Auto-generated from source. 4 struct(s) defined in this module.
 ## `src\mcp_client.py::MCPConfiguration`
 
 **Kind:** `dataclass`
-**Defined at:** line 111
+**Defined at:** line 110
 
 **Fields:**
 - `mcpServers: Dict[str, MCPServerConfig]`
@@ -14,7 +14,7 @@ Auto-generated from source. 4 struct(s) defined in this module.
 ## `src\mcp_client.py::MCPServerConfig`
 
 **Kind:** `dataclass`
-**Defined at:** line 85
+**Defined at:** line 84
 
 **Fields:**
 - `name: str`
@@ -27,7 +27,7 @@ Auto-generated from source. 4 struct(s) defined in this module.
 ## `src\mcp_client.py::RAGConfig`
 
 **Kind:** `dataclass`
-**Defined at:** line 156
+**Defined at:** line 155
 
 **Fields:**
 - `enabled: bool`
@@ -40,7 +40,7 @@ Auto-generated from source. 4 struct(s) defined in this module.
 ## `src\mcp_client.py::VectorStoreConfig`
 
 **Kind:** `dataclass`
-**Defined at:** line 125
+**Defined at:** line 124
 
 **Fields:**
 - `provider: str`

docs/type_registry/src_personas.md

@@ -5,7 +5,7 @@ Auto-generated from source. 1 struct(s) defined in this module.
 ## `src\personas.py::Persona`
 
 **Kind:** `dataclass`
-**Defined at:** line 21
+**Defined at:** line 20
 
 **Fields:**
 - `name: str`

docs/type_registry/src_tool_presets.md

@@ -5,7 +5,7 @@ Auto-generated from source. 2 struct(s) defined in this module.
 ## `src\tool_presets.py::Tool`
 
 **Kind:** `dataclass`
-**Defined at:** line 15
+**Defined at:** line 14
 
 **Fields:**
 - `name: str`
@@ -17,7 +17,7 @@ Auto-generated from source. 2 struct(s) defined in this module.
 ## `src\tool_presets.py::ToolPreset`
 
 **Kind:** `dataclass`
-**Defined at:** line 40
+**Defined at:** line 39
 
 **Fields:**
 - `name: str`

docs/type_registry/src_workspace_manager.md

@@ -5,7 +5,7 @@ Auto-generated from source. 1 struct(s) defined in this module.
 ## `src\workspace_manager.py::WorkspaceProfile`
 
 **Kind:** `dataclass`
-**Defined at:** line 13
+**Defined at:** line 12
 
 **Fields:**
 - `name: str`