Criptomart/red-supermercados-coop#6 add stock_valuation_layer_category_groupby

stock_valuation_layer_category_groupby/README.md

@@ -0,0 +1,57 @@
+# Stock Valuation Layer Category Groupby
+
+## Description
+
+This module allows grouping by product category in the stock valuation layer reports.
+
+### Problem
+
+By default, the `categ_id` field in `stock.valuation.layer` is a related field without storage (`store=False`). This means it cannot be used for grouping in reports and pivot views, even though it can be used for filtering and searching.
+
+### Solution
+
+This module makes the `categ_id` field stored (`store=True`) and indexed, which enables:
+- Grouping by product category in list views
+- Grouping by product category in pivot views
+- Grouping by product category in graph views
+- Better performance when filtering by category
+
+## Installation
+
+1. Install the module from the Apps menu
+2. The field will be automatically populated for existing records
+
+## Usage
+
+After installation:
+1. Go to Inventory > Reporting > Inventory Valuation
+2. Switch to Pivot or Graph view
+3. Click on "Measures" or group options
+4. You will now see "Product Category" available for grouping
+
+## Technical Details
+
+The module extends `stock.valuation.layer` model and modifies the `categ_id` field to:
+- `store=True`: Store the value in the database
+- `index=True`: Add database index for better performance
+
+The field remains a related field, so it will automatically update when the product category changes.
+
+## Bug Tracker
+
+Bugs are tracked on [GitHub Issues](https://github.com/OCA/stock-logistics-warehouse/issues).
+
+## Credits
+
+### Contributors
+
+* Criptomart
+
+### Maintainers
+
+This module is maintained by the OCA.
+
+## Compatibility
+
+- Odoo 16.0
+- stock_account