feat: Implement OAuth license activation flow

- Add LicenseConnect.tsx focused OAuth confirmation page in customer SPA
- Add /licenses/oauth/validate and /licenses/oauth/confirm API endpoints
- Update App.tsx to render license-connect outside BaseLayout (no header/footer)
- Add license_activation_method field to product settings in Admin SPA
- Create LICENSING_MODULE.md with comprehensive OAuth flow documentation
- Update API_ROUTES.md with license module endpoints

API_ROUTES.md

@@ -109,6 +109,31 @@ GET    /analytics/orders            # Order analytics
 GET    /analytics/customers         # Customer analytics
 ```
 
+### Licensing Module (`LicensesController.php`)
+```
+# Admin Endpoints (admin auth required)
+GET    /licenses                     # List licenses (with pagination, search)
+GET    /licenses/{id}                # Get single license
+POST   /licenses                     # Create license
+PUT    /licenses/{id}                # Update license
+DELETE /licenses/{id}                # Delete license
+
+# Public Endpoints (for client software validation)
+POST   /licenses/validate            # Validate license key
+POST   /licenses/activate            # Activate license on domain
+POST   /licenses/deactivate          # Deactivate license from domain
+
+# OAuth Endpoints (user auth required)
+GET    /licenses/oauth/validate      # Validate OAuth state and license ownership
+POST   /licenses/oauth/confirm       # Confirm activation and generate token
+```
+
+**Implementation Details:**
+- **List:** Supports pagination (`page`, `per_page`), search by key/email
+- **activate:** Supports Simple API and OAuth modes
+- **OAuth flow:** `oauth/validate` + `oauth/confirm` for secure user verification
+- See `LICENSING_MODULE.md` for full OAuth flow documentation
+
 ---
 
 ## Conflict Prevention Rules