docs(10): checkpoint - waves 1-3 complete, wave 4 pending

Completed:
- 10-01: Orphan cleanup (2 nodes removed)
- 10-02: Container Update sub-workflow (31 nodes)
- 10-03: Container Actions sub-workflow (8 nodes)
- 10-04: Integration verified with user

Pending:
- 10-05: Wire batch ops to sub-workflows, extract logs

Key fixes applied:
- n8n typeVersion 1.2 requires __rl resource locator format
- Docker 204 success detection via empty response check

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.planning/phases/10-workflow-modularization/10-02-SUMMARY.md

@@ -0,0 +1,59 @@
+---
+phase: 10-workflow-modularization
+plan: 02
+subsystem: infra
+tags: [n8n, workflow, modularization, sub-workflow, update]
+
+requires:
+  - phase: 10-01
+    provides: Clean workflow baseline (246 nodes)
+provides:
+  - Container Update sub-workflow (n8n-container-update.json)
+  - Main workflow wired to call sub-workflow for updates
+affects: [10-03, 10-04, 10-05]
+
+tech-stack:
+  added: [n8n Execute Sub-workflow]
+  patterns: [Resource locator format for workflowId (__rl: true)]
+
+key-files:
+  created: [n8n-container-update.json]
+  modified: [n8n-workflow.json]
+
+key-decisions:
+  - "Use resource locator format for workflowId (required for typeVersion 1.2)"
+  - "Sub-workflow handles update execution, main workflow handles confirmation UI"
+
+completed: 2026-02-04
+---
+
+# Phase 10 Plan 2: Container Update Sub-workflow Summary
+
+**Extracted container update flow to dedicated sub-workflow**
+
+## Accomplishments
+
+- Created `n8n-container-update.json` (31 nodes)
+- Wired main workflow to call sub-workflow for text and callback update paths
+- Reduced main workflow from 246 to 200 nodes (-46 nodes)
+
+## Key Files
+
+- `n8n-container-update.json` - New sub-workflow with full update logic
+- `n8n-workflow.json` - Added Execute Sub-workflow nodes
+
+## Technical Notes
+
+- n8n typeVersion 1.2 requires `workflowId` in resource locator format:
+  ```json
+  "workflowId": { "__rl": true, "mode": "list", "value": "<id>" }
+  ```
+- Sub-workflow ID: `7AvTzLtKXM2hZTio92_mC`
+
+## Issues Encountered
+
+- Initial "workflow not found" error due to plain string workflowId format
+- Fixed by converting to resource locator format with `__rl: true`
+
+---
+*Phase: 10-workflow-modularization | Completed: 2026-02-04*