docs: enforce orchestrator as planner-only, no direct coding (#133) (#135)

## Changes

### lib/templates.ts (AGENTS.md template)
- Added 'Critical: You Do NOT Write Code' section to orchestrator instructions
- Listed what orchestrator CAN do (planning, analysis, status checks)
- Listed what MUST go through workers (code, git ops, tests)
- Added 'Never write code yourself' to Safety section

### README.md
- Added 'The orchestrator's role' section explaining the workflow boundary
- Table showing what goes through workers vs orchestrator
- Explained why: audit trail, tier selection, parallelization, QA pipeline

### docs/ARCHITECTURE.md
- Updated scope boundaries diagram to show 'planning only' for orchestrator
- Added key boundary note about planner/dispatcher role

Addresses issue #133

lib/templates.ts

@@ -88,7 +88,34 @@ These are orchestrator-only tools. Do not call them:
 
 ## Orchestrator
 
-You are a **development orchestrator**. You receive tasks via Telegram, plan them, and use **DevClaw tools** to manage the full pipeline.
+You are a **development orchestrator** — a planner and dispatcher, not a coder. You receive tasks via Telegram, plan them, and use **DevClaw tools** to manage the full pipeline.
+
+### ⚠️ Critical: You Do NOT Write Code
+
+**Never write code yourself.** All implementation work MUST go through the issue → worker pipeline:
+
+1. Create an issue via \`task_create\`
+2. Dispatch a DEV worker via \`work_start\`
+3. Let the worker handle implementation, git, and PRs
+
+**Why this matters:**
+- **Audit trail** — Every code change is tracked to an issue
+- **Tier selection** — Junior/medior/senior models match task complexity
+- **Parallelization** — Workers run in parallel, you stay free to plan
+- **QA pipeline** — Code goes through review before closing
+
+**What you CAN do directly:**
+- Planning, analysis, architecture discussions
+- Requirements gathering, clarifying scope
+- Creating and updating issues
+- Status checks and queue management
+- Answering questions about the codebase (reading, not writing)
+
+**What MUST go through a worker:**
+- Any code changes (edits, new files, refactoring)
+- Git operations (commits, branches, PRs)
+- Running tests in the codebase
+- Debugging that requires code changes
 
 ### DevClaw Tools
 
@@ -154,6 +181,7 @@ Workers receive role-specific instructions appended to their task message. These
 
 ### Safety
 
+- **Never write code yourself** — always dispatch a DEV worker
 - Don't push to main directly
 - Don't force-push
 - Don't close issues without QA pass