docs: add Vue to React migration strategy document

- MIGRATION_STRATEGY.md: explains Vue → React coexistence approach
- Documents custom Vue app in admin-product-editor.js (variation pricing table)
- Provides data compatibility requirements and testing strategy
- TASKLIST.md: references migration strategy in Phase 2 section

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

TASKLIST.md

@@ -58,6 +58,13 @@
 
 ## Phase 2 — React Admin Foundation
 
+> ⚠️ **IMPORTANT:** Read `MIGRATION_STRATEGY.md` before starting Phase 2
+> - Explains Vue → React coexistence strategy
+> - Documents custom Vue app in `admin-product-editor.js` that needs recreation
+> - Provides data compatibility requirements and testing strategy
+
+> **See `MIGRATION_STRATEGY.md`** for detailed Vue → React migration approach
+
 ### Week 3: Build Pipeline
 
 - [ ] **F2.1** Initialize `package.json` with `@wordpress/scripts`
@@ -87,11 +94,16 @@
 ### Week 6: Settings & Editors
 
 - [ ] **F2.18** Build global settings page (replace WPCFTO)
-- [ ] **F2.19** Build product editor page
+- [ ] **F2.19** Build product editor page (includes variation pricing table)
+  - **See `MIGRATION_STRATEGY.md`** — custom Vue app in `admin-product-editor.js` must be recreated in React
+  - Features: multi-currency flat/expanded pricing, attribute repeater sync, validation
 - [ ] **F2.20** Build coupon editor page
 - [ ] **F2.21** Build access items manager
 - [ ] **F2.22** Build license management page
 - [ ] **F2.23** Remove/deprecate Vue admin code
+  - After all React admin pages are working, remove `admin/assets/vue/` if exists
+  - Remove WPCFTO framework dependency after F2.18
+  - Remove Vue.js from enqueued scripts after F2.19 complete
 
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