Sprint: Jobs scherm (#209)

* refactor(jobs): extraheer job-mapper naar lib/jobs-mapper.ts + voeg breadcrumb-velden toe

Verplaatst JobWithRelations, JOB_INCLUDE, RawJob, PriceRow, pickDescription,
computeCost en mapJob naar lib/jobs-mapper.ts (zonder 'use server'). Voegt
buildPriceMap helper toe en breidt de types uit met productCode, storyCode en
pbiCode via task->story->pbi en product.code includes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* feat(jobs): voeg GET /api/jobs/[id] route toe + tests

* feat(jobs): useJobsRealtime fetch-on-unknown met dedup-Set

Wanneer een SSE-event een onbekend job_id bevat, haalt de hook de volledige
job op via GET /api/jobs/[id] en upsert die in de store. Een inFlight-Set
voorkomt gelijktijdige dubbele fetches voor hetzelfde job_id. Bekende jobs
blijven de bestaande partial-upsert gebruiken. Zelfde logica in jobs_initial.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* feat(jobs): JobCard breadcrumb + datum-fallback per kind

Voeg productCode/pbiCode/storyCode/startedAt/finishedAt toe aan
JobCardProps; bouw breadcrumb per job-kind en toon finishedAt → startedAt
→ createdAt als datum. JobsColumn geeft de nieuwe velden door.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* test(jobs): JobCard breadcrumb + datum-fallback tests

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

__tests__/app/api/jobs/job-by-id-route.test.ts

@@ -0,0 +1,106 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+const { mockGetSession, mockFindFirstJob, mockFindManyPrice } = vi.hoisted(() => ({
+  mockGetSession: vi.fn(),
+  mockFindFirstJob: vi.fn(),
+  mockFindManyPrice: vi.fn(),
+}))
+
+vi.mock('@/lib/auth', () => ({ getSession: mockGetSession }))
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    claudeJob: { findFirst: mockFindFirstJob },
+    modelPrice: { findMany: mockFindManyPrice },
+  },
+}))
+
+import { GET } from '@/app/api/jobs/[id]/route'
+
+function makeParams(id = 'job-1'): { params: Promise<{ id: string }> } {
+  return { params: Promise.resolve({ id }) }
+}
+
+function makeRequest(id = 'job-1'): Request {
+  return new Request(`http://localhost/api/jobs/${id}`)
+}
+
+const RAW_JOB = {
+  id: 'job-1',
+  kind: 'TASK_IMPLEMENTATION' as const,
+  status: 'DONE' as const,
+  model_id: 'claude-sonnet-4-6',
+  input_tokens: 100,
+  output_tokens: 50,
+  cache_read_tokens: 0,
+  cache_write_tokens: 0,
+  branch: 'feat/test',
+  pr_url: null,
+  error: null,
+  summary: 'Done',
+  verify_result: 'ALIGNED' as const,
+  started_at: new Date('2026-01-01T10:00:00Z'),
+  finished_at: new Date('2026-01-01T10:05:00Z'),
+  created_at: new Date('2026-01-01T09:59:00Z'),
+  sprint_run_id: null,
+  task: {
+    code: 'T-42',
+    title: 'Some task',
+    description: null,
+    implementation_plan: 'Do the thing',
+    story: { code: 'S-10', pbi: { code: 'PBI-5' } },
+  },
+  idea: null,
+  product: { name: 'Scrum4Me', code: 'SCR' },
+  sprint_run: null,
+}
+
+describe('GET /api/jobs/:id', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockGetSession.mockResolvedValue({ userId: 'user-1' })
+    mockFindFirstJob.mockResolvedValue(RAW_JOB)
+    mockFindManyPrice.mockResolvedValue([])
+  })
+
+  it('returns 401 when not logged in', async () => {
+    mockGetSession.mockResolvedValue({ userId: undefined })
+    const res = await GET(makeRequest() as never, makeParams())
+    expect(res.status).toBe(401)
+    const body = await res.json()
+    expect(body.error).toBeTruthy()
+  })
+
+  it('returns 404 when job not found', async () => {
+    mockFindFirstJob.mockResolvedValue(null)
+    const res = await GET(makeRequest() as never, makeParams())
+    expect(res.status).toBe(404)
+    const body = await res.json()
+    expect(body.error).toBeTruthy()
+  })
+
+  it('queries with user_id filter to prevent cross-user access', async () => {
+    await GET(makeRequest() as never, makeParams())
+    expect(mockFindFirstJob).toHaveBeenCalledWith(
+      expect.objectContaining({
+        where: { id: 'job-1', user_id: 'user-1' },
+      })
+    )
+  })
+
+  it('returns 200 with mapped job shape including breadcrumb codes', async () => {
+    const res = await GET(makeRequest() as never, makeParams())
+    expect(res.status).toBe(200)
+    const body = await res.json()
+    expect(body).toMatchObject({
+      id: 'job-1',
+      kind: 'TASK_IMPLEMENTATION',
+      status: 'DONE',
+      taskCode: 'T-42',
+      taskTitle: 'Some task',
+      productCode: 'SCR',
+      storyCode: 'S-10',
+      pbiCode: 'PBI-5',
+      branch: 'feat/test',
+    })
+  })
+})