Add Phase 8: lesson plan templates with deep-copy instantiation

- New tables: lesson_plan_template, lesson_plan_template_section, lesson_plan_template_item
- skill_level enum: beginner, intermediate, advanced, all_levels
- Templates are reusable curriculum definitions independent of any member/enrollment
- POST /lesson-plan-templates/:id/create-plan deep-copies the template into a member plan
- Instantiation uses template name as default plan title, accepts custom title override
- Instantiation deactivates any existing active plan on the enrollment (one-active rule)
- Plan items are independent copies — renaming the template does not affect existing plans
- 11 new integration tests

packages/shared/src/schemas/lessons.schema.ts

@@ -200,6 +200,51 @@ export const LessonPlanItemUpdateSchema = z.object({
 })
 export type LessonPlanItemUpdateInput = z.infer<typeof LessonPlanItemUpdateSchema>
 
+// --- Lesson Plan Template schemas ---
+
+export const SkillLevel = z.enum(['beginner', 'intermediate', 'advanced', 'all_levels'])
+export type SkillLevel = z.infer<typeof SkillLevel>
+
+const TemplateItemInput = z.object({
+  title: z.string().min(1).max(255),
+  description: opt(z.string()),
+  gradingScaleId: opt(z.string().uuid()),
+  targetGradeValue: opt(z.string().max(50)),
+  sortOrder: z.coerce.number().int(),
+})
+
+const TemplateSectionInput = z.object({
+  title: z.string().min(1).max(255),
+  description: opt(z.string()),
+  sortOrder: z.coerce.number().int(),
+  items: z.array(TemplateItemInput).default([]),
+})
+
+export const LessonPlanTemplateCreateSchema = z.object({
+  name: z.string().min(1).max(255),
+  description: opt(z.string()),
+  instrument: opt(z.string().max(100)),
+  skillLevel: SkillLevel.default('all_levels'),
+  sections: z.array(TemplateSectionInput).default([]),
+})
+export type LessonPlanTemplateCreateInput = z.infer<typeof LessonPlanTemplateCreateSchema>
+
+export const LessonPlanTemplateUpdateSchema = z.object({
+  name: z.string().min(1).max(255).optional(),
+  description: opt(z.string()),
+  instrument: opt(z.string().max(100)),
+  skillLevel: SkillLevel.optional(),
+  isActive: z.boolean().optional(),
+})
+export type LessonPlanTemplateUpdateInput = z.infer<typeof LessonPlanTemplateUpdateSchema>
+
+export const TemplateInstantiateSchema = z.object({
+  memberId: z.string().uuid(),
+  enrollmentId: z.string().uuid(),
+  title: opt(z.string().min(1).max(255)),
+})
+export type TemplateInstantiateInput = z.infer<typeof TemplateInstantiateSchema>
+
 // --- Grade History schemas ---
 
 export const GradeCreateSchema = z.object({