feat(course): treatment courses with protocol-driven session planning

Laser is six to eight sessions; the previous design only knew single
appointments, which is the exception rather than the rule.

- CourseProtocol per service: session count and three distinct spacings —
  min is the earliest that is clinically allowed, ideal is best, max is where
  the course starts losing its effect
- Starting a course creates every session up front as `planned` and copies the
  protocol's numbers and per-session params, so changing the protocol tomorrow
  leaves a running course alone
- Suggestions anchor on the last *completed* session, not the course start:
  when session 2 slips, session 3 moves with it
- Slots are ranked by distance from ideal, not by earliest available — day 21
  is worse than day 27 when 28 is the target
- book-all is all-or-nothing inside one transaction, with a moving anchor and a
  90-day horizon; sessions past the horizon stay planned and are reported, not
  treated as failures
- The effective minimum is the stricter of the protocol and the task-09 spacing
  policy, so a clinic rule never fights the protocol
- Cancelling one session returns only that session to planned; abandoning a
  course does not cancel its appointments, which stays an explicit decision

One active course per (patient, service) via active_course_key, the same
partial-uniqueness trick as Appointment::activeSlotKey.

Admin: CourseProtocolsPage, TreatmentCoursePage and a courses tab on the
patient record.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

assets/admin/components/layout/SettingsLayout.tsx

@@ -2,7 +2,7 @@ import React from 'react';
 import {
   CreditCardIcon, UserIcon, CalendarDaysIcon, BuildingOffice2Icon,
   BanknotesIcon, UsersIcon, ShieldCheckIcon,
-  TagIcon, ChatBubbleLeftRightIcon, UserCircleIcon, UserPlusIcon, ReceiptPercentIcon, MapPinIcon, CubeIcon, ScaleIcon, RectangleStackIcon,
+  TagIcon, ChatBubbleLeftRightIcon, UserCircleIcon, UserPlusIcon, ReceiptPercentIcon, MapPinIcon, CubeIcon, ScaleIcon, RectangleStackIcon, ArrowPathRoundedSquareIcon,
 } from '@heroicons/react/24/outline';
 import PurchaseSubscriptionSidebar from './PurchaseSubscriptionSidebar';
 
@@ -34,6 +34,7 @@ export const SETTINGS_MENU: SettingsMenuItem[] = [
   { key: 'holidays',     label: 'تعطیلات رسمی',       icon: CalendarDaysIcon,         to: '/admin/holidays',             roles: ['doctor', 'clinic'], perm: ['appointment_settings', 'view'] },
   { key: 'policies',     label: 'قوانین',             icon: ScaleIcon,                to: '/admin/policies',             roles: ['doctor', 'clinic'], perm: ['appointment_settings', 'view'] },
   { key: 'packages',     label: 'پکیج‌ها',            icon: RectangleStackIcon,       to: '/admin/packages',             roles: ['doctor', 'clinic'], perm: ['appointment_settings', 'view'] },
+  { key: 'course-protocols', label: 'پروتکل دوره',    icon: ArrowPathRoundedSquareIcon, to: '/admin/course-protocols',   roles: ['doctor', 'clinic'], perm: ['appointment_settings', 'view'] },
   { key: 'payment',      label: 'مدیریت پرداخت',      icon: BanknotesIcon,            to: '/admin/my-financial',         perm: ['payments', 'view'] },
   { key: 'secretary',    label: 'مدیریت منشی',        icon: UsersIcon,                to: '/admin/my-secretaries' },
   { key: 'staff',        label: 'پرسنل',              icon: UserPlusIcon,             to: '/admin/staff',                perm: ['staff', 'view'] },