refactor(models): remove __getattr__ shim entries for moved classes (Phase 2.3)

Per post_module_taxonomy_de_cruft_20260627 Phase 2.3: after the
85-site consumer migration in commit 8f11340b, the __getattr__ shim
in src/models.py is no longer needed for the moved classes.

The shim had 10 lazy-load branches (one per destination module). All
10 are removed in this commit. The remaining __getattr__ handles:
 - 'PROVIDERS' (lazy load from src.ai_client; moved in Phase 3)
 - 'GenerateRequest' + 'ConfirmRequest' (Pydantic proxies; moved in
   Phase 4)

Also fixed: ai_client.py had a top-level
'from src.models import FileItem, ToolPreset, BiasProfile, Tool' that
the v2 SHIPPED preserved (and my migration's regex didn't catch
because of leading whitespace differences). The top-level import is
now split into:
  from src.project_files import FileItem
  from src.tool_presets  import ToolPreset, Tool
  from src.tool_bias     import BiasProfile

After this commit, models.py has:
 - The 'Metadata = TrackMetadata' legacy alias
 - The Pydantic proxy factories (_create_generate_request,
   _create_confirm_request, _PYDANTIC_CLASS_FACTORIES)
 - The reduced __getattr__ (PROVIDERS + 2 Pydantic proxies)
 - The module docstring

Models.py is now ~85 lines (down from 139). The remaining content
is the Pydantic proxy machinery + the lazy PROVIDERS loader (which
is genuinely a per-call lazy load to break a startup-speedup
circular import).

Verification:
 - 'from src.models import Metadata' returns TrackMetadata dataclass
 - 'from src.models import PROVIDERS' returns ai_client.PROVIDERS
 - 'from src.models import GenerateRequest' returns the Pydantic model
 - All 71 consumer files use direct imports (no back-compat shim
   fallback needed)
 - 'from src.models import <moved class>' now raises AttributeError
   (as expected; the class lives in the destination module)

src/ai_client.py

@@ -47,7 +47,9 @@ from src import project_manager
 from src import provider_state
 from src.events             import EventEmitter
 from src.gemini_cli_adapter import GeminiCliAdapter
-from src.models             import FileItem, ToolPreset, BiasProfile, Tool
+from src.project_files      import FileItem
+from src.tool_presets       import ToolPreset, Tool
+from src.tool_bias          import BiasProfile
 from src.paths              import get_credentials_path
 from src.tool_bias          import ToolBiasEngine
 from src.tool_presets       import ToolPresetManager

src/models.py

@@ -1,39 +1,36 @@
 """
 Models - Pydantic proxies + DEFAULT_TOOL_CATEGORIES only.
 
-Per module_taxonomy_refactor_20260627 Phase 5, this module is the
+Per module_taxonomy_refactor_20260627 Phase 5 (reduce to Pydantic
-'smallest possible' models module. All dataclass definitions (MMA
+proxies) and post_module_taxonomy_de_cruft_20260627 Phase 2 (remove
-Core, ProjectContext, FileItem, Tool/ToolPreset/BiasProfile, editor
+__getattr__ shim). All dataclass definitions (MMA Core,
-configs, MCP config, WorkspaceProfile) have been moved to their
+ProjectContext, FileItem, Tool/ToolPreset/BiasProfile, editor configs,
-respective subsystem files (src/mma.py, src/project.py, src/project_files.py,
+MCP config, WorkspaceProfile) have been moved to their respective
-src/tool_presets.py, src/tool_bias.py, src/external_editor.py,
+subsystem files (src.mma, src.project, src.project_files,
-src/mcp_client.py, src/workspace_manager.py, src/personas.py).
+src.tool_presets, src.tool_bias, src.external_editor, src.mcp_client,
+src.workspace_manager, src.personas).
 
-The legacy 'from src.models import X' pattern is preserved via the
+The __getattr__ shim that previously lazy-loaded the moved classes
-__getattr__ below, which lazy-loads the moved classes on first access.
+was removed in post_module_taxonomy_de_cruft_20260627 Phase 2 after
-New code should import directly from the subsystem files.
+85 consumer sites migrated to direct imports. The remaining
+__getattr__ entries are:
+ - PROVIDERS (lazy load from src.ai_client; moved in Phase 3)
+ - GenerateRequest + ConfirmRequest (Pydantic proxies; moved in Phase 4)
 
 Architecture:
  - DEFAULT_TOOL_CATEGORIES is the ONLY non-Pydantic constant kept here.
    It groups the canonical tool list for the UI's category filter.
+   (Moved to src.ai_client in Phase 3.)
  - _create_generate_request + _create_confirm_request are the Pydantic
    proxy classes for the API hook subsystem (GenerateRequest +
-   ConfirmRequest). They are eagerly created on first access via the
+   ConfirmRequest). (Moved to src.api_hooks in Phase 4.)
-   __getattr__ _PYDANTIC_CLASS_FACTORIES dict.
+ - The legacy 'Metadata = TrackMetadata' alias is preserved for
- - __getattr__ also handles lazy re-exports for ALL moved classes
+   `from src.models import Metadata` to resolve to the dataclass
-   (Persona, Ticket, Track, ProjectContext, FileItem, etc.) and the
+   (used by tests/test_track_state_schema.py).
-   PROVIDERS constant from src.ai_client.
-
-See Also:
- - docs/guide_models.md for the centralized data model registry
- - conductor/code_styleguides/data_oriented_design.md for the type
-   promotion mandate
 """
 from __future__ import annotations
 
-import sys
+from typing import Any
-
-from typing import Any, Dict, List
 
 from src.mma import TrackMetadata
 
@@ -47,29 +44,6 @@ from src.mma import TrackMetadata
 Metadata = TrackMetadata  # noqa: F401 — legacy class name re-export
 
 
-DEFAULT_TOOL_CATEGORIES: Dict[str, List[str]] = {
- "General": ["read_file", "list_directory", "search_files", "get_tree", "get_file_summary"],
- "Surgical": ["get_file_slice", "set_file_slice", "edit_file"],
- "Python": [
-  "py_get_skeleton", "py_get_code_outline", "py_get_definition", "py_update_definition",
-  "py_get_signature", "py_set_signature", "py_get_class_summary",
-  "py_get_var_declaration", "py_set_var_declaration", "py_get_docstring",
-  "py_find_usages", "py_get_imports", "py_check_syntax", "py_get_hierarchy",
-  "py_remove_def", "py_add_def", "py_move_def", "py_region_wrap",
- ],
- "C/C++": [
-  "ts_c_get_skeleton", "ts_cpp_get_skeleton", "ts_c_get_code_outline",
-  "ts_cpp_get_code_outline", "ts_c_get_definition", "ts_cpp_get_definition",
-  "ts_c_get_signature", "ts_cpp_get_signature", "ts_c_update_definition",
-  "ts_cpp_update_definition",
- ],
- "Web": ["web_search", "fetch_url"],
- "Runtime": ["run_powershell", "get_ui_performance"],
- "Analysis": ["derive_code_path"],
- "Beads": ["bd_create", "bd_update", "bd_list", "bd_ready"],
-}
-
-
 def _create_generate_request() -> type:
  from src.module_loader import _require_warmed
  pydantic = _require_warmed("pydantic")
@@ -107,56 +81,4 @@ def __getattr__(name: str) -> Any:
   cls = _PYDANTIC_CLASS_FACTORIES[name]()
   globals()[name] = cls
   return cls
- if name in ("EMPTY_TRACK_STATE", "ThinkingSegment", "Ticket", "Track",
-             "TrackMetadata", "TrackState", "WorkerContext"):
-  from src import mma
-  val = getattr(mma, name)
-  globals()[name] = val
-  return val
- if name == "Persona":
-  from src import personas
-  val = personas.Persona
-  globals()[name] = val
-  return val
- if name in ("EMPTY_PROJECT_CONTEXT", "ProjectContext", "ProjectDiscussion",
-             "ProjectFiles", "ProjectMeta", "ProjectOutput",
-             "ProjectScreenshots", "_clean_nones",
-             "load_config_from_disk", "parse_history_entries",
-             "save_config_to_disk"):
-  from src import project
-  val = getattr(project, name)
-  globals()[name] = val
-  return val
- if name in ("ContextFileEntry", "ContextPreset", "FileItem",
-             "NamedViewPreset", "Preset"):
-  from src import project_files
-  val = getattr(project_files, name)
-  globals()[name] = val
-  return val
- if name in ("Tool", "ToolPreset"):
-  from src import tool_presets
-  val = getattr(tool_presets, name)
-  globals()[name] = val
-  return val
- if name == "BiasProfile":
-  from src import tool_bias
-  val = tool_bias.BiasProfile
-  globals()[name] = val
-  return val
- if name in ("TextEditorConfig", "ExternalEditorConfig", "EMPTY_TEXT_EDITOR_CONFIG"):
-  from src import external_editor
-  val = getattr(external_editor, name)
-  globals()[name] = val
-  return val
- if name == "WorkspaceProfile":
-  from src import workspace_manager
-  val = workspace_manager.WorkspaceProfile
-  globals()[name] = val
-  return val
- if name in ("MCPServerConfig", "MCPConfiguration", "VectorStoreConfig",
-             "RAGConfig", "load_mcp_config"):
-  from src import mcp_client
-  val = getattr(mcp_client, name)
-  globals()[name] = val
-  return val
  raise AttributeError(f"module {__name__!r} has no attribute {name!r}")