docs(guides): fix stale src/models.py refs + line-number drift across 11 guides

Sweep of the per-source-file guides + Readme.md for stale references
to src/models.py as the data model home. models.py is now a ~1.5KB
re-export shim per module_taxonomy_refactor_20260627; dataclasses
moved to src/mma.py, src/project_files.py, src/type_aliases.py,
src/mcp_tool_specs.py, src/result_types.py, src/context_presets.py,
src/workspace_manager.py, src/personas.py.

- guide_gui_2.md: _gui_func line 754->1062; render_main_interface
  line 1259->1898.
- python.md §10 exemption table: App gui_2.py:307->314; AppController
  795->801; RAGEngine 123->125; HookServer 856->941;
  HookServerInstance 130->171; HookHandler 155->208;
  WebSocketServer 908->993.
- guide_multi_agent_conductor.md: Ticket now in src/mma.py (not
  models.py); ConductorEngine 116+->112+; WorkerPool 50-114->52-110.
- guide_agent_memory_dimensions.md: FileItem ref models.py:510-559
  -> src/project_files.py.
- guide_context_aggregation.md: FileItem + ContextPreset refs ->
  src/project_files.py + src/context_presets.py; ai_client _send_*
  count 5->8.
- guide_discussions.md: parse_history_entries now in src/mma.py;
  ContextPreset/FileItem cross-refs updated.
- guide_personas.md: Persona now in src/personas.py; import example
  updated.
- guide_rag.md: RAGConfig now in src/mcp_client.py.
- guide_workspace_profiles.md: WorkspaceProfile now in
  src/workspace_manager.py.
- guide_mma.md: Data Structures section notes src/mma.py as the live
  location.
- Readme.md: MMA Engine + Data Models rows updated for the
  models.py shim reality + 8 providers + mma_exec deprecation.
- guide_ai_client.md: '5 provider SDKs'->8 (added note); PROVIDERS
  line 56->62; __getattr__ re-export line 261->31; provider
  switching examples use real registered model names (claude-sonnet-
  4-5, MiniMax-M2, gemini-2.5-flash, qwen-plus, grok-2, llama-3.1);
  _provider union lists all 8 providers.

docs/guide_discussions.md

@@ -28,7 +28,7 @@ This is a *deliberate* design choice. Manual Slop treats the discussion as user-
 
 ### The Entry Dict
 
-The smallest unit of a discussion is the **entry**, a `dict[str, Any]` with this shape (`src/models.py:parse_history_entries` builds it; `src/gui_2.py:render_discussion_entry` reads it):
+The smallest unit of a discussion is the **entry**, a `dict[str, Any]` with this shape (`parse_history_entries` builds it — moved out of `src/models.py` to `src/mma.py` per `module_taxonomy_refactor_20260627`; `src/gui_2.py:render_discussion_entry` reads it):
 
 | Field | Type | Source | Purpose |
 |---|---|---|---|
@@ -343,7 +343,7 @@ The POST endpoint allows external automation to *replace* the entire discussion.
 
 ## Cross-References
 
-- **Discussion data model:** `src/models.py:196 parse_history_entries`, `src/models.py:909 ContextPreset`, `src/models.py:510 FileItem`
+- **Discussion data model:** `parse_history_entries` (moved out of `src/models.py` to `src/mma.py`), `ContextPreset` (now in `src/context_presets.py`), `FileItem` (now in `src/project_files.py`)
 - **Discussion persistence:** `src/project_manager.py:429 branch_discussion`, `src/project_manager.py:447 promote_take`, `src/project_manager.py:396 calculate_track_progress`
 - **Discussion switching/management:** `src/app_controller.py:3199 _switch_discussion`, `src/app_controller.py:3225 _flush_disc_entries_to_project`, `src/app_controller.py:3286 _handle_reset_session`, `src/app_controller.py:3357 _handle_compress_discussion`, `src/app_controller.py:3503 _branch_discussion`, `src/app_controller.py:3521 _rename_discussion`, `src/app_controller.py:3537 _delete_discussion`
 - **GUI render functions:** `src/gui_2.py:175 truncate_entries`, `src/gui_2.py:735 _take_snapshot`, `src/gui_2.py:754 _apply_snapshot`, `src/gui_2.py:3770 render_discussion_entry`, `src/gui_2.py:4227 render_discussion_entries`, `src/gui_2.py:4239 render_discussion_entry_controls`, `src/gui_2.py:4317 render_discussion_roles`, `src/gui_2.py:4330 render_discussion_selector`