Replace Meshkee password when linking an existing account to a new site.

Cross-site register now updates the password to the signup value and documents passwordUpdated for storefronts.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/PROJECT_CONTEXT.md

@@ -253,7 +253,7 @@ All routes are prefixed with `/api/v1`.
 
 | Method | Path | Description |
 |--------|------|-------------|
-| POST | `/auth/register` | Customer registration by domain |
+| POST | `/auth/register` | Customer registration by domain. Cross-site link updates Meshkee password to the new signup password (`passwordUpdated`). |
 | POST | `/auth/login` | Cell + password |
 | POST | `/auth/login-otp` | Passwordless login with SMS OTP |
 | POST | `/auth/reset-password` | Reset password with SMS OTP |

docs/website-api/AI_PROMPT.md

@@ -23,7 +23,7 @@ You are building a **Meshkee business website (storefront)**. You must use the M
 1. Resolve tenant first: `GET /tenants/<WEBSITE_DOMAIN>` → save `businessId` from `id`.
 2. All public content uses `/tenants/<WEBSITE_DOMAIN>/...` (no auth).
 3. Cart, orders, favorites use `/businesses/<businessId>/...` with `Authorization: Bearer <accessToken>`.
-4. Customer register body must include `"domain": "<WEBSITE_DOMAIN>"`. If the cell already exists on another Meshkee site and the password differs, API returns `409` with `CELL_EXISTS_OTHER_SITE:...`. Retry register with `"acknowledgeExistingAccount": true` to link that account (password/profile stay unchanged), then complete SMS OTP.
+4. Customer register body must include `"domain": "<WEBSITE_DOMAIN>"`. If the cell already exists on another Meshkee site and the password differs, API returns `409` with `CELL_EXISTS_OTHER_SITE:...`. Retry register with `"acknowledgeExistingAccount": true` to link that account (profile unchanged; **password is replaced** with the new signup password), then complete SMS OTP.
 5. Cell numbers are E.164 (`+98912...`).
 6. Do not call dashboard/CMS routes (`/businesses/.../products` write APIs, media upload, domain-admin, etc.).
 7. **Partner SMS** (`POST /public/sms/send`) is for external partner backends with an issued `X-Api-Key` only — not for normal storefront UI. See https://api.meshkee.com/docs/website/SMS.md

docs/website-api/openapi.json

@@ -1557,7 +1557,7 @@
                   },
                   "acknowledgeExistingAccount": {
                     "type": "boolean",
-                    "description": "If true, link an existing Meshkee account from another website without matching its password. Existing password and profile stay unchanged."
+                    "description": "If true, link an existing Meshkee account from another website without matching its password. Profile stays unchanged; password is replaced with the new signup password. Response may include passwordUpdated: true."
                   }
                 }
               }

src/auth/auth.service.ts

@@ -97,10 +97,19 @@ export class AuthService {
       }
     }
 
+    const linkedExistingAccount = Boolean(existingUser);
+
     const user = await this.prisma.$transaction(async (tx) => {
-      const account =
-        existingUser ??
-        (await tx.user.create({
+      let account = existingUser;
+
+      if (account) {
+        // Cross-site join: replace Meshkee password with the one entered on this signup.
+        account = await tx.user.update({
+          where: { id: account.id },
+          data: { passwordHash },
+        });
+      } else {
+        account = await tx.user.create({
           data: {
             cellNumber: dto.cellNumber,
             passwordHash,
@@ -109,7 +118,8 @@ export class AuthService {
             lastName: dto.lastName,
             cellVerifiedAt: smsEnabled ? null : new Date(),
           },
-        }));
+        });
+      }
 
       await tx.businessCustomer.create({
         data: {
@@ -143,10 +153,15 @@ export class AuthService {
     const tokens = await this.issueTokens(authUser);
 
     return {
-      message: smsEnabled
-        ? 'Registration successful. Please verify your cell number with OTP.'
-        : 'Registration successful. SMS verification is disabled — account auto-verified.',
+      message: linkedExistingAccount
+        ? smsEnabled
+          ? 'Joined this website. Your Meshkee password was updated to the one you just entered. Please verify your cell number with OTP.'
+          : 'Joined this website. Your Meshkee password was updated to the one you just entered.'
+        : smsEnabled
+          ? 'Registration successful. Please verify your cell number with OTP.'
+          : 'Registration successful. SMS verification is disabled — account auto-verified.',
       smsEnabled,
+      passwordUpdated: linkedExistingAccount,
       user: this.serializeUser(authUser),
       registeredBusiness: {
         id: business.id,

src/auth/dto/register.dto.ts

@@ -37,7 +37,8 @@ export class RegisterDto {
 
   /**
    * When true, link an existing Meshkee account (other websites) to this tenant
-   * without requiring the existing password. Existing password and profile stay unchanged.
+   * without requiring the existing password. Profile stays unchanged; the password
+   * is replaced with the one submitted in this registration.
    */
   @IsOptional()
   @IsBoolean()

src/website-docs/static/AI_PROMPT.md

@@ -23,7 +23,7 @@ You are building a **Meshkee business website (storefront)**. You must use the M
 1. Resolve tenant first: `GET /tenants/<WEBSITE_DOMAIN>` → save `businessId` from `id`.
 2. All public content uses `/tenants/<WEBSITE_DOMAIN>/...` (no auth).
 3. Cart, orders, favorites use `/businesses/<businessId>/...` with `Authorization: Bearer <accessToken>`.
-4. Customer register body must include `"domain": "<WEBSITE_DOMAIN>"`. If the cell already exists on another Meshkee site and the password differs, API returns `409` with `CELL_EXISTS_OTHER_SITE:...`. Retry register with `"acknowledgeExistingAccount": true` to link that account (password/profile stay unchanged), then complete SMS OTP.
+4. Customer register body must include `"domain": "<WEBSITE_DOMAIN>"`. If the cell already exists on another Meshkee site and the password differs, API returns `409` with `CELL_EXISTS_OTHER_SITE:...`. Retry register with `"acknowledgeExistingAccount": true` to link that account (profile unchanged; **password is replaced** with the new signup password), then complete SMS OTP.
 5. Cell numbers are E.164 (`+98912...`).
 6. Do not call dashboard/CMS routes (`/businesses/.../products` write APIs, media upload, domain-admin, etc.).
 7. **Partner SMS** (`POST /public/sms/send`) is for external partner backends with an issued `X-Api-Key` only — not for normal storefront UI. See https://api.meshkee.com/docs/website/SMS.md

src/website-docs/static/openapi.json

@@ -1557,7 +1557,7 @@
                   },
                   "acknowledgeExistingAccount": {
                     "type": "boolean",
-                    "description": "If true, link an existing Meshkee account from another website without matching its password. Existing password and profile stay unchanged."
+                    "description": "If true, link an existing Meshkee account from another website without matching its password. Profile stays unchanged; password is replaced with the new signup password. Response may include passwordUpdated: true."
                   }
                 }
               }