[ADD] product_origin_char: Free text origin field per supplier

New addon to replace structured country/state fields with flexible
free-text origin descriptions.

Features:
- Translatable origin_text field in product.supplierinfo
- Computed origin field in products based on main_seller_id
- Support for creative supplier origin descriptions
- Full OCA documentation structure
- ES/EU translations included
- 8 unit tests (all passing)

Replaces product_origin for use cases where suppliers use non-standardized
origin descriptions (e.g., 'Valencia, Spain', 'Huerta de...', etc.)

Depends on: product, product_main_seller
Author: Criptomart
Funding: Elika Bilbo

product_origin_char/README.rst

@@ -0,0 +1,155 @@
+==================
+Product Origin Text
+==================
+
+..
+   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+   !! This file is generated by oca-gen-addon-readme !!
+   !! changes will be overwritten.                   !!
+   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+   !! source digest: sha256:todo
+   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+.. |badge1| image:: https://img.shields.io/badge/maturity-Beta-yellow.png
+    :target: https://odoo-community.org/page/development-status
+    :alt: Beta
+.. |badge2| image:: https://img.shields.io/badge/licence-AGPL--3-blue.png
+    :target: http://www.gnu.org/licenses/agpl-3.0-standalone.html
+    :alt: License: AGPL-3
+
+|badge1| |badge2|
+
+This module replaces the structured country/state origin fields from ``product_origin``
+with a flexible free-text field that can be defined per supplier.
+
+**Problem:**
+
+The standard ``product_origin`` module provides structured fields (country + state) for
+product origin. However, suppliers often use creative and varied formats to describe
+product origin:
+
+* "Valencia, Spain"
+* "Huerta de Ana, Aragón"
+* "Organic Farm - Northern Italy"
+* "Local producer - Basque Country"
+* "Fair Trade - Colombia"
+
+These free-form descriptions don't fit into structured country/state fields.
+
+**Solution:**
+
+This module adds a translatable ``origin_text`` field to ``product.supplierinfo`` that:
+
+* Allows free-form text to describe product origin
+* Is stored per supplier (different suppliers may have different origin info)
+* Is translatable (can be described differently in each language)
+* Is automatically displayed on the product based on the main vendor
+  (from ``product_main_seller`` module)
+
+**Features:**
+
+* Free-text ``Origin`` field in supplier info (Purchase tab of product)
+* Computed ``Origin`` field in product form (shows main vendor's origin)
+* Field is visible in product list view (optional column)
+* Full translation support for multiple languages
+* Compatible with existing supplier management workflows
+
+**Table of contents**
+
+.. contents::
+   :local:
+
+Installation
+============
+
+This module depends on:
+
+* ``product`` - Base product management
+* ``product_main_seller`` - To determine the main vendor for products
+
+To install:
+
+#. Install the required dependencies
+#. Install this module through the Odoo Apps menu
+
+Configuration
+=============
+
+No configuration is needed. The module works automatically after installation.
+
+The origin text displayed on a product is based on the **main vendor** as determined
+by ``product_main_seller`` (the first supplier in the vendors list).
+
+Usage
+=====
+
+**To add origin information to a product:**
+
+#. Go to a product form
+#. Open the **Purchase** tab
+#. In the **Vendors** section, select a supplier line
+#. Fill in the **Origin** field with free-form text describing the origin
+   (e.g., "Valencia, Huerta de..., Spain")
+#. Save the product
+
+**To view origin information:**
+
+* The **Origin** field will be automatically displayed on the product form
+  (below the **Main Vendor** field in the Purchase tab)
+* The origin shown is from the **main vendor** (first supplier in the list)
+* You can also add the Origin column to product list views
+
+**To change the displayed origin:**
+
+* Reorder the vendors list to change which is the main vendor
+* The origin text will automatically update to show the new main vendor's origin
+
+**Multi-language support:**
+
+* The origin text is translatable
+* Switch to another language and edit the supplier info to provide a translation
+* Each language can have a different description of the origin
+
+Bug Tracker
+===========
+
+Bugs are tracked on `Criptomart GitLab Issues
+<https://git.criptomart.net/criptomart/addons-cm/issues>`_.
+
+In case of trouble, please check there if your issue has already been reported.
+If you spotted it first, help us to smash it by providing a detailed and welcomed
+feedback.
+
+Credits
+=======
+
+Contributors
+------------
+
+* `Criptomart <https://criptomart.net>`_:
+
+  * Development and implementation
+
+Financiers
+----------
+
+**Development:**
+
+* `Criptomart <https://criptomart.net>`_
+
+**Funding:**
+
+* `Elika Bilbo <https://elikabilbo.eus>`_
+
+This module was developed by Criptomart with funding from Elika Bilbo.
+
+Maintainers
+-----------
+
+This module is maintained by Criptomart.
+
+.. image:: https://criptomart.net/logo.png
+   :alt: Criptomart
+   :target: https://criptomart.net
+
+This module is part of the `addons-cm <https://git.criptomart.net/criptomart/addons-cm>`_ project.