feat(mentor): admin preview + send mentorship welcome/reminder email

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/unit/mentorship-welcome-send.test.ts

@@ -0,0 +1,107 @@
+import { describe, it, expect, beforeAll, afterAll, vi } from 'vitest'
+
+vi.mock('@/lib/email', async () => {
+  const actual = await vi.importActual<typeof import('@/lib/email')>('@/lib/email')
+  return {
+    ...actual,
+    sendMentorBulkAssignmentEmail: vi.fn(async () => true),
+    sendTeamMentorIntroductionEmail: vi.fn(async () => true),
+  }
+})
+
+import { prisma, createCaller } from '../setup'
+import {
+  createTestProgram,
+  createTestCompetition,
+  createTestRound,
+  createTestProject,
+  createTestProjectRoundState,
+  createTestUser,
+  cleanupTestData,
+} from '../helpers'
+import { mentorRouter } from '../../src/server/routers/mentor'
+import {
+  sendMentorBulkAssignmentEmail,
+  sendTeamMentorIntroductionEmail,
+} from '@/lib/email'
+
+describe('mentor.sendMentorshipWelcome / previewMentorshipWelcome', () => {
+  let programId: string
+  const userIds: string[] = []
+  let roundId: string
+  let memberEmail: string
+  let mentorEmail: string
+
+  beforeAll(async () => {
+    const program = await createTestProgram()
+    programId = program.id
+    const competition = await createTestCompetition(program.id)
+    const round = await createTestRound(competition.id, {
+      roundType: 'MENTORING',
+      status: 'ROUND_ACTIVE',
+    })
+    roundId = round.id
+
+    const project = await createTestProject(program.id)
+    await createTestProjectRoundState(project.id, round.id)
+
+    const mentor = await createTestUser('MENTOR')
+    const member = await createTestUser('APPLICANT')
+    mentorEmail = mentor.email
+    memberEmail = member.email
+    userIds.push(mentor.id, member.id)
+
+    await prisma.teamMember.create({
+      data: { projectId: project.id, userId: member.id, role: 'LEAD' },
+    })
+    await prisma.mentorAssignment.create({
+      data: { projectId: project.id, mentorId: mentor.id, method: 'MANUAL' },
+    })
+  })
+
+  afterAll(async () => {
+    await cleanupTestData(programId, userIds)
+  })
+
+  it('sends to mentors and team members and reports counts', async () => {
+    const admin = await createTestUser('SUPER_ADMIN')
+    userIds.push(admin.id)
+    const caller = createCaller(mentorRouter, {
+      id: admin.id,
+      email: admin.email,
+      role: 'SUPER_ADMIN',
+    })
+
+    const res = await caller.sendMentorshipWelcome({ roundId, customNote: 'Reminder!' })
+
+    expect(res.sent).toBeGreaterThan(0)
+    expect(sendMentorBulkAssignmentEmail).toHaveBeenCalled()
+    expect(sendTeamMentorIntroductionEmail).toHaveBeenCalled()
+  })
+
+  it('does NOT stamp the one-time flags (re-sendable reminder)', async () => {
+    const assignment = await prisma.mentorAssignment.findFirst({
+      where: { project: { projectRoundStates: { some: { roundId } } } },
+    })
+    expect(assignment?.notificationSentAt).toBeNull()
+    expect(assignment?.teamIntroducedAt).toBeNull()
+  })
+
+  it('preview returns non-empty mentor + team HTML with real contacts', async () => {
+    const admin = await createTestUser('SUPER_ADMIN')
+    userIds.push(admin.id)
+    const caller = createCaller(mentorRouter, {
+      id: admin.id,
+      email: admin.email,
+      role: 'SUPER_ADMIN',
+    })
+
+    const pv = await caller.previewMentorshipWelcome({ roundId })
+
+    expect(pv.recipientCount).toBeGreaterThan(0)
+    expect(pv.html).toContain('Mentor version')
+    expect(pv.html).toContain('Team version')
+    expect(pv.html).toContain(memberEmail)
+    expect(pv.html).toContain(mentorEmail)
+  })
+})