When multiple talent records share the same information, opening the Talent Pools smart button from a matching application will trigger a traceback.

Steps to reproduce the error:
- Install ``hr_recruitment`` module with demo data
- Go to Recruitment > Applications > Talent Pools > Create a new pool
- Go to Recruitment > Applications > All Applications > Create a new application with valid email >
  Click Add to Pool > Select the Talent Pool > Add to Pool
- Duplicate the created talent record
- Create another application with the same email > save > click Talent Pools

Traceback:
```py
ValueError: Expected singleton: hr.applicant(2, 1)
```

https://github.com/odoo/odoo/blob/d4e76a5663223a2a2c6e50d1701fabbdcaf32405/addons/hr_recruitment/models/hr_applicant.py#L857-L859
Here, the talent is searched using matching applicant information.
When a matching talent has been duplicated, the search returns multiple records.
Assigning a multi-records to the many2one field ``pool_applicant_id`` then raises a singleton error.

Solution:
Restrict the duplication of talent.

sentry-7556261128

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Description of the issue/feature this PR addresses:
The rating module does not correctly extend the mail modules onClick for NotificationItem

Current behavior before PR:
* mail NotificationItem onClick calls `this.onClickThread(isMarkAsRead, thread, message)`
* rating NotificationItem onClick calls `this.onClickThread(isMarkAsRead, thread)`
  * causing the [if in onClickThread](https://github.com/odoo/odoo/blob/18.0/addons/mail/static/src/core/public_web/messaging_menu.js#L39C17-L39C24) to be missed and falling backup to opening the thread
     ```javascript
            if (message?.needaction && message.message_type === "user_notification") {
                this.store.inbox.highlightMessage = message;
                this.openDiscussion(this.store.inbox);
                return;
            }
            this.openDiscussion(thread);
            return;
     ```

Desired behavior after PR is merged:
* rating should not change the fallback behaviour for messages without a rating_id and still allow opening the user_notification in inbox instead of switching to the thread

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Info @wt-io-it

Forward-Port-Of: odoo/odoo#244521

When generating an offer from the recruitment application and signing it, the applicant's email address is incorrectly displayed.

### **Steps to Reproduce:**
1) Install sign, recruitment, hr_contract_salary
2) Create an new application and add basic detail like name and email as
   (path and `path@test.com`)
3) Generate offer and sign with all the required signer(applicant and Marc Demo). 
4) Open the application form view and open the certificate.

### **Observed Behavior:**
Email is not set correctly in the generated certificate (appearing as `john@example.com`).

### **Expected Behavior:**
The email of the applicant should be correctly set(e.g as `path@test.com`)

### **Root Cause:**
When the applicant signs the document, their email is explicitly set to `False` at [1]. This is done because the applicant is not linked to any user yet. Later, when generating the certificate, the system attempts to display the user's partner email at [2], which is `False`, causing the default fallback value (`john@example.com`) to be printed.

[1]- https://github.com/odoo/enterprise/blob/49226f4109c7d7bb48340949951e70f4245d0e5b/hr_contract_salary/controllers/main.py#L53-L54

[2]- https://github.com/odoo/enterprise/blob/49226f4109c7d7bb48340949951e70f4245d0e5b/sign/report/sign_log_reports.xml#L59

### **Fix:**
Use `signer_email` instead of the partner's email to ensure the correct email is displayed on the certificate every time.

opw-6280170

Forward-Port-Of: odoo/enterprise#120566