feat(fusion_accounting_assets): asset category template model

- defaults applied to new assets (method, useful_life, declining rate,
  salvage %, prorate convention)
- GL account hooks: asset_account_id, depreciation_account_id,
  expense_account_id (domain-filtered to relevant account types)
- computed asset_count for kanban / list views
- 3 new tests (55 total)

Made-with: Cursor

fusion_accounting_assets/models/fusion_asset_category.py

@@ -1,10 +1,6 @@
-"""Asset categories with default settings (used as templates).
+"""Asset categories with default settings (used as templates)."""
 
-Stub created with Task 8 (so fusion.asset.category_id Many2one resolves).
-Fully elaborated in Task 10.
-"""
-
-from odoo import fields, models
+from odoo import api, fields, models
 
 
 class FusionAssetCategory(models.Model):
@@ -14,3 +10,44 @@ class FusionAssetCategory(models.Model):
 
     name = fields.Char(required=True, translate=True)
     sequence = fields.Integer(default=10)
+    company_id = fields.Many2one(
+        'res.company', default=lambda self: self.env.company,
+    )
+
+    method = fields.Selection([
+        ('straight_line', 'Straight Line'),
+        ('declining_balance', 'Declining Balance'),
+        ('units_of_production', 'Units of Production'),
+    ], default='straight_line', required=True)
+    useful_life_years = fields.Integer(default=5)
+    declining_rate_pct = fields.Float(default=20.0)
+    salvage_value_pct = fields.Float(
+        default=0.0,
+        help="% of cost (used for new assets in this category).",
+    )
+    prorate_convention = fields.Selection([
+        ('full_month', 'Full Month'),
+        ('days_365', 'Days / 365'),
+        ('days_period', 'Days in Period'),
+    ], default='days_period', required=True)
+
+    asset_account_id = fields.Many2one(
+        'account.account', string='Asset Account',
+        domain="[('account_type', 'in', ('asset_fixed', 'asset_non_current'))]",
+    )
+    depreciation_account_id = fields.Many2one(
+        'account.account', string='Depreciation Account',
+        domain="[('account_type', '=', 'asset_fixed')]",
+    )
+    expense_account_id = fields.Many2one(
+        'account.account', string='Expense Account',
+        domain="[('account_type', '=', 'expense_depreciation')]",
+    )
+
+    asset_count = fields.Integer(compute='_compute_asset_count')
+
+    def _compute_asset_count(self):
+        for cat in self:
+            cat.asset_count = self.env['fusion.asset'].search_count([
+                ('category_id', '=', cat.id),
+            ])