conductor(track): Initialize 'architecture_boundary_hardening' track

conductor/tracks/architecture_boundary_hardening_20260302/plan.md

@@ -0,0 +1,23 @@
+# Implementation Plan: Architecture Boundary Hardening
+
+Architecture reference: [docs/guide_architecture.md](../../../docs/guide_architecture.md)
+
+---
+
+## Phase 1: Patch Context Amnesia Leak (Meta-Tooling)
+Focus: Stop `mma_exec.py` from injecting massive full-text dependencies.
+
+- [ ] Task 1.1: In `scripts/mma_exec.py`, completely remove the `UNFETTERED_MODULES` constant and its associated `if dep in UNFETTERED_MODULES:` check. Ensure all imported local dependencies strictly use `generate_skeleton()`.
+
+## Phase 2: Seal the HITL Bypass (Application Core)
+Focus: Ensure native MCP mutating tools cannot execute without user approval in the `manual_slop` application.
+
+- [ ] Task 2.1: In `mcp_client.py`, define a new constant set `MUTATING_TOOLS = {"set_file_slice", "py_update_definition", "py_set_signature", "py_set_var_declaration"}`. (Note: `write_file` is not currently in the tool list, but add it if it is).
+- [ ] Task 2.2: In `ai_client.py`'s provider loops (`_send_gemini`, `_send_gemini_cli`, `_send_anthropic`, `_send_deepseek`), update the tool execution logic. If `name in mcp_client.MUTATING_TOOLS`, it MUST trigger the `pre_tool_callback` (or a variation of it) to ask for user approval before calling `mcp_client.dispatch`.
+- [ ] Task 2.3: In `gui_2.py`, ensure the UI rendering for the pending tool approval handles the AST mutations gracefully (e.g. showing the `new_content` payload instead of a PowerShell script).
+
+## Phase 3: DAG Engine Cascading Blocks (Application Core)
+Focus: Prevent infinite deadlocks when Tier 3 workers fail repeatedly.
+
+- [ ] Task 3.1: In `dag_engine.py`, add a `cascade_blocks()` method to `TrackDAG`. This method should iterate through all `todo` tickets and if any of their dependencies are `blocked`, mark the ticket itself as `blocked`.
+- [ ] Task 3.2: In `multi_agent_conductor.py`, update `ConductorEngine.run()`. Before calling `self.engine.tick()`, call `self.track_dag.cascade_blocks()` (or equivalent) so that blocked states propagate cleanly, allowing the `all_done` or block detection logic to exit the while loop correctly.