Deepen all business modules: methods, validations, workflows

Account:
- action_post: partner validation, line count check, sequence number
  assignment (JOURNAL/YYYY/NNNN format)
- action_register_payment: opens payment wizard from invoice
- remove_move_reconcile: undo reconciliation, reset residuals
- Register Payment button in invoice form (visible when posted+unpaid)

Sale:
- action_cancel: cancels linked draft invoices + SO state
- action_draft: reset cancelled SO to draft
- action_view_invoice: navigate to linked invoices
- Cancel/Reset buttons in form view header

Purchase:
- button_draft: reset cancelled PO to draft
- action_create_bill already existed

Stock:
- action_cancel on picking: cancels moves + picking state

CRM:
- action_set_won_rainbowman: sets Won stage + rainbow effect
- convert_opportunity: lead→opportunity type switch

HR:
- hr.contract model (name, employee, wage, dates, state)

Project:
- action_blocked on task (kanban_state)
- Task stage seed data (New, In Progress, Done, Cancelled)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

addons/crm/models/crm.go

@@ -105,6 +105,38 @@ func initCRMLead() {
 		}
 		return true, nil
 	})
+
+	// convert_opportunity: alias for convert_to_opportunity
+	m.RegisterMethod("convert_opportunity", func(rs *orm.Recordset, args ...interface{}) (interface{}, error) {
+		env := rs.Env()
+		for _, id := range rs.IDs() {
+			env.Tx().Exec(env.Ctx(),
+				`UPDATE crm_lead SET type = 'opportunity' WHERE id = $1`, id)
+		}
+		return true, nil
+	})
+
+	// action_set_won_rainbowman: set won stage + rainbow effect
+	m.RegisterMethod("action_set_won_rainbowman", func(rs *orm.Recordset, args ...interface{}) (interface{}, error) {
+		env := rs.Env()
+		// Find Won stage
+		var wonStageID int64
+		env.Tx().QueryRow(env.Ctx(),
+			`SELECT id FROM crm_stage WHERE is_won = true LIMIT 1`).Scan(&wonStageID)
+		if wonStageID == 0 {
+			wonStageID = 4 // fallback
+		}
+		for _, id := range rs.IDs() {
+			env.Tx().Exec(env.Ctx(),
+				`UPDATE crm_lead SET stage_id = $1, probability = 100 WHERE id = $2`, wonStageID, id)
+		}
+		return map[string]interface{}{
+			"effect": map[string]interface{}{
+				"type":    "rainbow_man",
+				"message": "Congrats, you won this opportunity!",
+			},
+		}, nil
+	})
 }
 
 // initCRMStage registers the crm.stage model.