[ADD] point_of_sale: documentation for pos-based marketing

This PR adds the documentation needed to use pos-based marketing.

In this PR, we introduce configuration and flow related to Email
and WhatsApp marketing in Point of Sale from storing contact details
to sending emails and WhatsApp messages from the point of sale.

task-4053075

closes odoo/documentation#11625

X-original-commit: 5aa54d4234
Signed-off-by: Loredana Perazzo (lrpz) <lrpz@odoo.com>
Co-authored-by: Anantkumar Parmar <paan@odoo.com>
Co-authored-by: Loredana Perazzo <lrpz@odoo.com>

content/applications/sales/point_of_sale.rst

@@ -186,4 +186,5 @@ the **POS dashboard**.
    point_of_sale/restaurant
    point_of_sale/pricing
    point_of_sale/payment_methods
+   point_of_sale/pos_based_marketing
    point_of_sale/reporting

content/applications/sales/point_of_sale/pos_based_marketing.rst

@@ -0,0 +1,120 @@
+==================
+Marketing features
+==================
+
+Use your POS system to engage with customers directly by sending them promotional offers via email
+or WhatsApp.
+
+Storing contact details
+=======================
+
+This feature requires your customer's contact details, either their email address or phone number.
+
+- **Email addresses**: automatically collected and saved in POS orders when sending a receipt by
+  email.
+- **Phone numbers**: to store phone numbers when sending receipts on WhatsApp or by SMS,
+
+  #. Go to :menuselection:`Configuration --> Settings` and scroll to the :guilabel:`Bills &
+     Receipts` section;
+  #. Activate the :guilabel:`WhatsApp Enabled` or :guilabel:`SMS Enabled` option(s).
+
+.. image:: pos_based_marketing/sms-whatsapp-enabled.png
+   :alt: setting to enable to store phone numbers when sending receipts
+
+If a customer’s contact information is missing, it will be automatically saved in POS orders when
+the receipt is sent via email, SMS, or WhatsApp.
+
+.. tip::
+   From a POS order form, navigate to the :guilabel:`Contact Info` category under the
+   :guilabel:`Extra Info` tab, then click the email icon or whatsapp icon to send standalone
+   marketing messages.
+
+   .. image:: pos_based_marketing/standalone-marketing-from-pos.png
+      :alt: pos orders form's standalone marketing message option
+
+Email marketing
+===============
+
+To send marketing emails to your customers from POS orders,
+
+#. Go to :menuselection:`Point of Sale --> Orders --> Orders`;
+#. Select the orders;
+#. Click :guilabel:`Actions`, then :guilabel:`Send Email` from the dropdown menu.
+
+Doing so opens an email composing form. Fill it in and hit :guilabel:`Send`.
+
+.. image:: pos_based_marketing/mail-composer.png
+   :alt: mail composer view
+   :scale: 50 %
+
+.. tip::
+   - Save some time by saving your content as a template. Click the vertical ellipsis button and
+     select your template under the :guilabel:`Insert Template` section.
+   - You can also save your content as template for later use. Click the vertical ellipsis button
+     and select :guilabel:`Save as Template`.
+
+.. note::
+   - Fill in the :guilabel:`Mass Mailing Name` field to create a mass mailing and track its results
+     in the :doc:`Email Marketing app <../../marketing/email_marketing>`.
+   - If an email address is not related to an existing customer, a new customer is automatically
+     created when sending marketing emails.
+
+.. seealso::
+   :doc:`Use the email marketing app for more advanced marketing features
+   <../../marketing/email_marketing>`.
+
+Whatsapp marketing
+==================
+
+.. _pos_based_marketing/whatsapp_config:
+
+Configuration
+-------------
+
+You first need to enable the related server action to send WhatsApp marketing messages from your POS
+using the phone numbers collected from POS orders. To do so,
+
+#. Go to the WhatsApp application;
+#. Create a new :ref:`WhatsApp template <WhatsApp/templates>`;
+#. Configure the fields:
+
+   - :guilabel:`Applies to` field set to :guilabel:`Point of Sale Orders`;
+   - :guilabel:`Category` field to :guilabel:`Marketing`;
+   - :guilabel:`Phone Field` to either :guilabel:`Mobile` or :guilabel:`Customer > Phone`.
+#. Click :guilabel:`Submit for Approval`;
+#. Once approved, click the :guilabel:`Allow Multi` button to create a server action in the POS
+   orders list view.
+
+.. image:: pos_based_marketing/whatsapp-template.png
+   :alt: approved and configured for marketing uses whatsapp template
+
+.. warning::
+   If you modify the template's content, you must request for approval again, as its status returns
+   to the :guilabel:`Draft` state.
+
+.. seealso::
+   :doc:`WhatsApp configuration <../../productivity/whatsapp>`
+
+Send WhatsApp marketing messages
+--------------------------------
+
+#. Go to :menuselection:`Point of Sale --> Orders --> Orders`;
+#. Select the orders;
+#. Click :guilabel:`Actions`, then :guilabel:`WhatsApp Message` from the dropdown menu.
+
+Doing so opens a WhatsApp message composing form. Select the desired marketing template in the
+:guilabel:`Template` field and hit :guilabel:`Send Message`.
+
+.. image:: pos_based_marketing/whatsapp-composer.png
+   :alt: whatsapp composer view
+
+.. note::
+   - To use WhatsApp marketing in the Point of Sale, approved marketing templates must have the
+     :guilabel:`Allow Multi` option enabled and :guilabel:`Point of Sale Orders` selected in the
+     :guilabel:`Applies to` field.
+   - If the server action is displayed without a properly configured template, an error message
+     appears. Click :guilabel:`Configure Templates` and complete the :ref:`WhatsApp setup
+     <pos_based_marketing/whatsapp_config>` steps.
+
+.. seealso::
+   :doc:`../../productivity/whatsapp`