feat(ideas): upload-plan knop — short-circuit van Make-Plan AI-flow (#197)

Voegt een 'Upload plan' knop toe in idea-row-actions (verschijnt in zowel
list als idea-detail). Klik → file picker → kies .md → server-side parse +
opslaan; idea-status springt naar PLAN_READY. Vandaaruit de bestaande
'Maak PBI' knop voor materialize.

Server (uploadPlanMdAction):
- Toegestaan vanuit DRAFT, GRILLED, PLAN_FAILED, PLAN_READY
- DRAFT → skip-grill: status gaat direct naar PLAN_READY
- PLAN_READY overschrijft het bestaande plan (consistent met
  updatePlanMdAction, geen confirmation)
- Geblokkeerd in GRILLING/PLANNING (job loopt), PLANNED (al gematerialiseerd)
- Parse-failure → 422 + details (NIET opslaan, zodat een onparseerbaar plan
  nooit in de DB belandt)
- Empty / >100k chars → 422
- Schrijft IdeaLog NOTE met from_status + length
- Rate-limit + demo-guard + ownership-check via loadOwnedIdea (zelfde
  patroon als updatePlanMdAction)

UI (idea-row-actions.tsx):
- Hidden <input type=file accept=".md,.markdown,text/markdown,text/plain">
- FileReader → text → action
- Toast bij success + router.refresh()
- Blocked-tooltip in andere statussen

Tests: 10 nieuwe in __tests__/actions/ideas-crud.test.ts dekkend voor:
happy paths (DRAFT/GRILLED/PLAN_READY-overwrite/PLAN_FAILED), blocks
(PLANNED/GRILLING), validation (empty/oversized/parse-fail), 404.
Full suite groen: 849/849.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

__tests__/actions/ideas-crud.test.ts

@@ -65,6 +65,7 @@ import {
   deleteIdeaAction,
   updateGrillMdAction,
   updatePlanMdAction,
+  uploadPlanMdAction,
   downloadIdeaMdAction,
   startGrillJobAction,
   startMakePlanJobAction,
@@ -251,6 +252,97 @@ body
   })
 })
 
+describe('uploadPlanMdAction', () => {
+  const VALID_PLAN = `---
+pbi:
+  title: Uploaded
+  priority: 2
+stories:
+  - title: S1
+    priority: 2
+    tasks:
+      - title: T1
+        priority: 2
+---
+
+body
+`
+
+  it('happy: uploads from DRAFT — skips grill, sets PLAN_READY', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'DRAFT' })
+    const r = await uploadPlanMdAction('idea-1', VALID_PLAN)
+    expect(r).toEqual({ success: true })
+    expect(m.$transaction).toHaveBeenCalled()
+    const txnArg = m.$transaction.mock.calls.at(-1)?.[0] as unknown[] | undefined
+    expect(txnArg).toBeDefined()
+    // The first call in the transaction is the update — confirm status=PLAN_READY.
+    expect(m.idea.update).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ plan_md: VALID_PLAN, status: 'PLAN_READY' }),
+      }),
+    )
+  })
+
+  it('happy: uploads from GRILLED', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'GRILLED' })
+    const r = await uploadPlanMdAction('idea-1', VALID_PLAN)
+    expect(r).toEqual({ success: true })
+  })
+
+  it('happy: overwrites existing plan from PLAN_READY', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'PLAN_READY' })
+    const r = await uploadPlanMdAction('idea-1', VALID_PLAN)
+    expect(r).toEqual({ success: true })
+  })
+
+  it('happy: uploads from PLAN_FAILED (retry)', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'PLAN_FAILED' })
+    const r = await uploadPlanMdAction('idea-1', VALID_PLAN)
+    expect(r).toEqual({ success: true })
+  })
+
+  it('rejects from PLANNED (already materialized)', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'PLANNED' })
+    const r = await uploadPlanMdAction('idea-1', VALID_PLAN)
+    expect(r).toMatchObject({ code: 422 })
+    expect(m.$transaction).not.toHaveBeenCalled()
+  })
+
+  it('rejects from GRILLING (job running)', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'GRILLING' })
+    const r = await uploadPlanMdAction('idea-1', VALID_PLAN)
+    expect(r).toMatchObject({ code: 422 })
+  })
+
+  it('rejects empty markdown', async () => {
+    const r = await uploadPlanMdAction('idea-1', '   \n  ')
+    expect(r).toMatchObject({ code: 422 })
+    // Should fail before touching DB
+    expect(m.idea.findFirst).not.toHaveBeenCalled()
+  })
+
+  it('rejects oversized markdown', async () => {
+    const huge = 'a'.repeat(100_001)
+    const r = await uploadPlanMdAction('idea-1', huge)
+    expect(r).toMatchObject({ code: 422 })
+    expect(m.idea.findFirst).not.toHaveBeenCalled()
+  })
+
+  it('rejects invalid yaml (parse-fail 422 with details)', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({ status: 'DRAFT' })
+    const r = await uploadPlanMdAction('idea-1', '# no frontmatter')
+    expect(r).toMatchObject({ code: 422 })
+    expect((r as { details?: unknown }).details).toBeDefined()
+    expect(m.$transaction).not.toHaveBeenCalled()
+  })
+
+  it('returns 404 when idea not found', async () => {
+    m.idea.findFirst.mockResolvedValueOnce(null)
+    const r = await uploadPlanMdAction('nope', VALID_PLAN)
+    expect(r).toMatchObject({ code: 404 })
+  })
+})
+
 describe('startGrillJobAction', () => {
   const idea = {
     id: 'idea-1',