[FIX+IMP+MIG] contract: Several refinements:

* Remove incorrect oldname attributes.
* Add filter on partners for running contracts (+ a support o2m field for that).
* Cover more tables in model renaming + cleaner code using a loop.
* Don't copy contract lines, but rename table + copy contract records on pre.
* Contract code is now populated to "Reference/Description" field in invoice.
* Order on new contract model has been restored to the same as old analytic accounts.

contract/models/abstract_contract_line.py

@@ -113,7 +113,6 @@ class ContractAbstractContractLine(models.AbstractModel):
         comodel_name='contract.abstract.contract',
         required=True,
         ondelete='cascade',
-        oldname='analytic_account_id',
     )
 
     @api.depends(

contract/models/contract.py

@@ -14,6 +14,7 @@ from odoo.tools.translate import _
 class ContractContract(models.Model):
     _name = 'contract.contract'
     _description = "Contract"
+    _order = 'code, name asc'
     _inherit = [
         'mail.thread',
         'mail.activity.mixin',
@@ -44,7 +45,6 @@ class ContractContract(models.Model):
         comodel_name='contract.line',
         inverse_name='contract_id',
         copy=True,
-        oldnae='contract_line_ids',
     )
 
     user_id = fields.Many2one(
@@ -273,7 +273,7 @@ class ContractContract(models.Model):
         if self.contract_type == 'purchase':
             invoice_type = 'in_invoice'
         return {
-            'reference': self.code,
+            'name': self.code,
             'type': invoice_type,
             'partner_id': self.invoice_partner_id.id,
             'currency_id': currency.id,

contract/models/contract_line.py

@@ -25,7 +25,6 @@ class ContractLine(models.Model):
         required=True,
         index=True,
         ondelete='cascade',
-        oldname='analytic_account_id',
     )
     analytic_account_id = fields.Many2one(
         string="Analytic account",

contract/models/contract_template.py

@@ -19,5 +19,4 @@ class ContractTemplate(models.Model):
         inverse_name='contract_id',
         copy=True,
         string='Contract template lines',
-        oldname='contract_line_ids',
     )

contract/models/res_partner.py

@@ -15,6 +15,11 @@ class ResPartner(models.Model):
         string='Purchase Contracts',
         compute='_compute_contract_count',
     )
+    contract_ids = fields.One2many(
+        comodel_name='contract.contract',
+        inverse='partner_id',
+        string="Contracts",
+    )
 
     def _compute_contract_count(self):
         contract_model = self.env['contract.contract']