[IMP] estate: implement business logic for offers, constraints, state transitions

This commit completes the enhancements from chapters 11 to 15 of the Odoo 18
Real Estate module. It introduces a range of improvements:

- Added state field with custom transitions (`new`, `offer received`,
`offer accepted`, `sold`, `cancelled`), including buttons and logic for
Sold/Cancelled.
- Added computed fields: total_area (living + garden), best_offer, and
selling_price.
- Added SQL constraints and Python constraints to ensure offers are above
a threshold and selling price is logically correct.
- Used computed and inverse fields to manage garden area visibility based on the
garden boolean.
- Refactored UI behavior (e.g., readonly fields) based on the state of the
property.
- Automatically assigns partner to offers upon creation.
- Used Inheritance for inheriting the class and use the features.
- Created kanban view while using drag and drop.

These changes reinforce business rules and improve usability for real estate
 agents managing listings and offers.

Author: raaa-odoo

rental_deposit/__init__.py

@@ -1 +1 @@
-from . import models
+from . import models

rental_deposit/__manifest__.py

@@ -14,4 +14,4 @@
             'deposit_rental/static/src/website_deposit_amount.js',
         }
     },
-}
+}

rental_deposit/models/__init__.py

@@ -1,4 +1,4 @@
 from . import res_config_settings
 from . import product_template
 from . import sale_order
-from . import sale_order_line
+from . import sale_order_line

rental_deposit/models/product_template.py

@@ -1,4 +1,5 @@
-from odoo import api, fields, models
+from odoo import fields, models
+
 
 class ProductTemplate(models.Model):
     _inherit = 'product.template'

rental_deposit/models/res_config_settings.py

@@ -1,5 +1,6 @@
 from odoo import api, fields, models
 
+
 class ResConfigSettings(models.TransientModel):
     _inherit = 'res.config.settings'
 

rental_deposit/models/sale_order.py

@@ -1,6 +1,7 @@
-from odoo import _, api, fields, models
+from odoo import _, models
 from odoo.exceptions import UserError
 
+
 class SaleOrder(models.Model):
     _inherit = 'sale.order'
 
@@ -14,7 +15,7 @@ def _add_deposit_product(self, order_line):
             raise UserError(_("The configured deposit product does not exist."))
 
         existing_line = self.order_line.filtered(lambda l: l.linked_line_id.id == order_line.id)
-        amount = order_line.product_id.deposit_amount * order_line.product_uom_qty
+        # amount = order_line.product_id.deposit_amount * order_line.product_uom_qty
 
         if existing_line:
             existing_line.write({
@@ -31,4 +32,4 @@ def _add_deposit_product(self, order_line):
                 'price_unit': order_line.product_id.deposit_amount,
                 'linked_line_id': order_line.id,
                 'name': f"Deposit for {order_line.product_id.display_name}",
-            })
+            })

rental_deposit/models/sale_order_line.py

@@ -1,5 +1,6 @@
 from odoo import api, fields, models
 
+
 class SaleOrderLine(models.Model):
     _inherit = 'sale.order.line'
 

rental_deposit/views/res_config_settings_views.xml

@@ -13,4 +13,4 @@
             </xpath>
         </field>
     </record>
-</odoo>
+</odoo>