feat(fusion_repairs): Bundle 6 - M7 failure analytics + M9 margin per repair

M9 margin per repair
- New non-stored computes on repair.order: x_fc_revenue, x_fc_labour_cost,
  x_fc_parts_cost, x_fc_margin, x_fc_margin_pct.
- Revenue: sum of posted out_invoice.amount_untaxed on the repair's sale
  order (handles partial / multi invoice scenarios).
- Labour: sum of (task.duration_hours x technician.x_fc_tech_cost_rate)
  over COMPLETED visits only - avoids counting scheduled-but-not-done time.
- Parts: sum of standard_price x qty for stock moves where
  repair_line_type='add' (parts consumed, not removed).
- New 'Margin' notebook tab on repair.order form, manager-group gated.

M7 failure analytics on the dashboard
- Three new keys in get_dashboard_data():
  * failures_by_product - top 8 products by repair_count in last 90 days
    via _read_group (efficient - no record load)
  * failures_by_symptom - top 8 x_fc_issue_category values
  * margin_summary - revenue/labour/parts/margin/margin_pct + sample_size
    over the same 90-day window
- Three new tiles on the OWL dashboard 'Last 90 Days' section:
  Margin Summary (revenue/labour/parts/margin breakdown),
  Failure Rate by Product, Failure Rate by Symptom.
- New formatMoney + formatPercent helpers on the dashboard JS so values
  display as 'CAD 12,345' rather than raw floats.

Verified end-to-end on local westin-v19:
  Dashboard returned all 9 expected keys.
  Top product: 'M6 X 27 THREADED BARREL' (2 repairs) - actual test data.
  Margin summary over 26 repairs (dev has $0 invoices so values 0.0,
  but the compute path is exercised and shapes are correct).

Bumped to 19.0.1.6.0.

Co-authored-by: Cursor <cursoragent@cursor.com>

fusion_repairs/models/repair_order.py

@@ -163,6 +163,63 @@ class RepairOrder(models.Model):
              'long-running repair (M3). Avoids re-posting daily.',
     )
 
+    # ------------------------------------------------------------------
+    # M9 - Margin per repair (revenue - labour cost - parts cost)
+    # All non-stored computes; surfaced in the M7 analytics dashboard.
+    # ------------------------------------------------------------------
+    x_fc_revenue = fields.Monetary(
+        string='Revenue',
+        currency_field='company_currency_id',
+        compute='_compute_margin',
+        help='Sum of posted invoice totals for the repair sale order.',
+    )
+    x_fc_labour_cost = fields.Monetary(
+        string='Labour Cost',
+        currency_field='company_currency_id',
+        compute='_compute_margin',
+        help='Sum of (hours x technician cost rate) over all completed visits.',
+    )
+    x_fc_parts_cost = fields.Monetary(
+        string='Parts Cost',
+        currency_field='company_currency_id',
+        compute='_compute_margin',
+        help='Sum of standard_price for parts consumed via repair operations.',
+    )
+    x_fc_margin = fields.Monetary(
+        string='Margin',
+        currency_field='company_currency_id',
+        compute='_compute_margin',
+        help='Revenue - labour cost - parts cost.',
+    )
+    x_fc_margin_pct = fields.Float(
+        string='Margin %',
+        compute='_compute_margin',
+    )
+
+    def _compute_margin(self):
+        for r in self:
+            revenue = 0.0
+            if r.sale_order_id and hasattr(r.sale_order_id, 'invoice_ids'):
+                for inv in r.sale_order_id.invoice_ids.filtered(
+                    lambda m: m.state == 'posted' and m.move_type == 'out_invoice'
+                ):
+                    revenue += inv.amount_untaxed or 0.0
+            labour = 0.0
+            for task in r.x_fc_technician_task_ids:
+                if task.status != 'completed':
+                    continue
+                rate = task.technician_id.x_fc_tech_cost_rate or 0.0
+                labour += (task.duration_hours or 0.0) * rate
+            parts = 0.0
+            for move in r.move_ids.filtered(lambda m: m.repair_line_type == 'add'):
+                parts += (move.product_id.standard_price or 0.0) * (move.product_uom_qty or 0.0)
+            r.x_fc_revenue = revenue
+            r.x_fc_labour_cost = labour
+            r.x_fc_parts_cost = parts
+            margin = revenue - labour - parts
+            r.x_fc_margin = margin
+            r.x_fc_margin_pct = (margin / revenue * 100) if revenue else 0.0
+
     def write(self, vals):
         # H2: stamp x_fc_done_at the first time state transitions to 'done'
         # so the NPS cron has a stable timestamp (write_date moves on every