feat(PBI-76): migrate cookie-based prefs to user-settings (Phase 2) (#189)

* feat(PBI-76): extend UserSettings schema with layout

Adds layout.splitPanePositions and layout.activeSprints. These will
hold values currently kept in client-side and server-side cookies
(Phase 2). Two new tests cover the shape.

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

* feat(PBI-76): migrate SplitPane positions to user-settings store

Outside of a drag the store is the source of truth (cross-tab
updates flow in for free). During a drag we keep splits in local
state so mousemove does not round-trip through the store. On
mouseup we persist the final splits via setPref. Removes
document.cookie reads/writes — cookieKey is reused as the
store-key for backwards compat.

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

* feat(PBI-76): resolveActiveSprint reads from User.settings

lib/active-sprint:
- New helpers: getActiveSprintIdFromSettings, setActiveSprintInSettings,
  clearActiveSprintInSettings — all read/write user.settings.layout.activeSprints.
- resolveActiveSprint(productId, userId) — userId now required, falls back
  to first OPEN, then most recent CLOSED sprint.
- Cookie helpers (getActiveSprintIdFromCookie/setActiveSprintCookie/
  clearActiveSprintCookie) removed.

Callers updated to pass session.userId. The cookie-based fallback path
is gone — `actions/active-sprint.ts` and `actions/sprints.ts` will be
updated in the next commit (T-917).

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

* feat(PBI-76): rewrite setActiveSprint callers to use settings

setActiveSprintAction, syncActiveSprintCookieAction, and the two
sprint-creation paths in actions/sprints.ts now write through
setActiveSprintInSettings (which also emits pg_notify for cross-tab
sync) instead of dropping a cookie. The action names keep the
'cookie' suffix in the user-visible API for now — clean rename can
come later.

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

* feat(PBI-76): migration helper v2 — handle legacy cookies

Bumps marker version to 'v2'. buildMigrationPatch now also scans
document.cookie for `sp:*` (split-pane positions) and
`active_sprint_*` (active sprint per product) and lifts them into
layout.splitPanePositions / layout.activeSprints. clearLegacyStorage
replaces clearLegacyLocalStorage and clears both keys and cookies.
clearLegacyLocalStorage stays as a deprecated alias so the bridge
upgrade is a single rename.

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

* test(PBI-76): align tests with new SplitPane and active-sprint flow

- split-pane.test.tsx: seed positions via Zustand store instead of
  document.cookie; mock @/actions/user-settings so the prisma client
  is not transitively initialised in jsdom.
- backlog-split-pane.test.tsx: same action mock.
- sprint-dates.test.ts: add user.findUnique/update + $executeRaw
  mocks because createSprintAction now writes to user-settings.

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

---------

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

__tests__/lib/user-settings-migration.test.ts

@@ -2,15 +2,25 @@ import { afterEach, beforeEach, describe, expect, it } from 'vitest'
 
 import {
   buildMigrationPatch,
-  clearLegacyLocalStorage,
+  clearLegacyStorage,
 } from '@/lib/user-settings-migration'
 
+function clearAllCookies() {
+  for (const part of document.cookie.split(';')) {
+    const eq = part.indexOf('=')
+    const name = (eq < 0 ? part : part.slice(0, eq)).trim()
+    if (name) document.cookie = `${name}=; max-age=0; path=/`
+  }
+}
+
 beforeEach(() => {
   localStorage.clear()
+  clearAllCookies()
 })
 
 afterEach(() => {
   localStorage.clear()
+  clearAllCookies()
 })
 
 describe('buildMigrationPatch', () => {
@@ -21,11 +31,42 @@ describe('buildMigrationPatch', () => {
     expect(result.legacyKeys).toEqual([])
   })
 
-  it('skips after marker is set', () => {
+  it('skips after marker is set to current version', () => {
+    localStorage.setItem('scrum4me:sprint_pb_filter_status', 'all')
+    localStorage.setItem('scrum4me:settings_migrated', 'v2')
+    const result = buildMigrationPatch()
+    expect(result.hasData).toBe(false)
+  })
+
+  it('still runs when only the v1 marker is set (re-migration)', () => {
     localStorage.setItem('scrum4me:sprint_pb_filter_status', 'all')
     localStorage.setItem('scrum4me:settings_migrated', 'v1')
     const result = buildMigrationPatch()
-    expect(result.hasData).toBe(false)
+    expect(result.hasData).toBe(true)
+  })
+
+  it('extracts split-pane cookies into layout', () => {
+    document.cookie = `sp:backlog-p1=${encodeURIComponent(JSON.stringify([25, 35, 40]))}; path=/`
+    const result = buildMigrationPatch()
+    expect(result.patch.layout?.splitPanePositions).toEqual({ 'backlog-p1': [25, 35, 40] })
+    expect(result.legacyCookies).toContain('sp:backlog-p1')
+  })
+
+  it('ignores split-pane cookies that do not sum to 100', () => {
+    document.cookie = `sp:bad=${encodeURIComponent(JSON.stringify([10, 20]))}; path=/`
+    const result = buildMigrationPatch()
+    expect(result.patch.layout).toBeUndefined()
+  })
+
+  it('extracts active-sprint cookies into layout.activeSprints', () => {
+    document.cookie = `active_sprint_prod-1=sprint-abc; path=/`
+    document.cookie = `active_sprint_prod-2=sprint-xyz; path=/`
+    const result = buildMigrationPatch()
+    expect(result.patch.layout?.activeSprints).toEqual({
+      'prod-1': 'sprint-abc',
+      'prod-2': 'sprint-xyz',
+    })
+    expect(result.legacyCookies).toContain('active_sprint_prod-1')
   })
 
   it('extracts sprint backlog prefs into nested patch', () => {
@@ -87,20 +128,20 @@ describe('buildMigrationPatch', () => {
   })
 })
 
-describe('clearLegacyLocalStorage', () => {
-  it('removes given keys and sets the marker', () => {
+describe('clearLegacyStorage', () => {
+  it('removes given keys and cookies and sets the v2 marker', () => {
     localStorage.setItem('scrum4me:sprint_pb_sort', 'code')
-    localStorage.setItem('scrum4me:pbi_sort', 'priority')
+    document.cookie = 'sp:x=foo; path=/'
 
-    clearLegacyLocalStorage(['scrum4me:sprint_pb_sort', 'scrum4me:pbi_sort'])
+    clearLegacyStorage(['scrum4me:sprint_pb_sort'], ['sp:x'])
 
     expect(localStorage.getItem('scrum4me:sprint_pb_sort')).toBeNull()
-    expect(localStorage.getItem('scrum4me:pbi_sort')).toBeNull()
-    expect(localStorage.getItem('scrum4me:settings_migrated')).toBe('v1')
+    expect(document.cookie).not.toContain('sp:x=foo')
+    expect(localStorage.getItem('scrum4me:settings_migrated')).toBe('v2')
   })
 
-  it('sets marker even with empty keys list (no-op migration)', () => {
-    clearLegacyLocalStorage([])
-    expect(localStorage.getItem('scrum4me:settings_migrated')).toBe('v1')
+  it('sets marker even with empty lists (no-op migration)', () => {
+    clearLegacyStorage([], [])
+    expect(localStorage.getItem('scrum4me:settings_migrated')).toBe('v2')
   })
 })

__tests__/lib/user-settings.test.ts

@@ -109,7 +109,17 @@ describe('UserSettingsSchema', () => {
         jobsColumns: { 'queue:active': { kinds: ['TASK_IMPLEMENTATION'], statuses: [] } },
       },
       devTools: { debugMode: true },
+      layout: {
+        splitPanePositions: { 'backlog-pid': [25, 35, 40] },
+        activeSprints: { 'product-1': 'sprint-1' },
+      },
     })
     expect(result.success).toBe(true)
   })
+
+  it('accepts layout-only settings', () => {
+    expect(UserSettingsSchema.safeParse({
+      layout: { splitPanePositions: { x: [50, 50] }, activeSprints: { p: 's' } },
+    }).success).toBe(true)
+  })
 })