feat(PBI-76): user-settings DB-store infrastructure (Phase 0) (#185)

* docs(PBI-76): plan for user-settings DB-store

Persists view/filter prefs in User.settings (Json) instead of
localStorage. SSR-correct hydration, cross-tab sync via
LISTEN/NOTIFY + SSE, cross-device persistence.

Phased: 0=infra, 1=migrate flicker sources, 2=cookie consolidation.

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

* feat(PBI-76): User.settings json column + migration

Adds JSONB column to users table for persistent user prefs.
Idempotent SQL — safe on databases where column already exists.

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

* feat(PBI-76): user-settings types and merge helpers

Zod schema for User.settings shape (views/devTools), deep-merge
helper that replaces arrays and merges nested objects, and a
safe parser that returns defaults on invalid input.

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

* feat(PBI-76): updateUserSettingsAction with notify

Validates patch via Zod, deep-merges with current settings in
a transaction, persists to DB, and emits pg_notify on
scrum4me_changes for cross-tab/cross-device sync. Demo accounts
get 403, unauthenticated 401, invalid input 422.

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

* feat(PBI-76): user-settings zustand store with optimistic flow

Hydrate from prop (SSR-correct), setPref via path with optimistic
update + rollback on server error, applyServerPatch for SSE-driven
cross-tab updates. Demo accounts skip server-write entirely.

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

* feat(PBI-76): SSE route for user-settings

User-scoped /api/realtime/user-settings stream that filters
scrum4me_changes notifications on kind=user_settings and matching
userId. Forwards the patch as a data: event so other tabs can
applyServerPatch without re-fetching settings.

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

* feat(PBI-76): user-settings bridge mounted in app layout

Hydrates the zustand store with the user's persisted settings via
prop (SSR-correct, no flicker). Opens an EventSource to
/api/realtime/user-settings so changes from other tabs/devices
flow into the same store. Demo accounts skip the SSE subscription.

Layout now selects user.settings alongside the other user fields,
no extra DB roundtrip.

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

* test(PBI-76): user-settings lib/action/store coverage

22 vitest cases covering merge semantics (no mutation, array
replace, nested merge), Zod schema strictness, server action
auth/demo/validation paths, and the optimistic store flow
including rollback and demo-mode skip.

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

* chore(PBI-76): sync package-lock to v1.3.3

Lockfile drifted after @prisma/client reinstall during the
schema regenerate. No dependency changes — just the version
field tracking package.json bumped in #184.

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

---------

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

docs/INDEX.md

@@ -62,6 +62,7 @@ Auto-generated on 2026-05-10 from front-matter and headings.
 | [ST-1114 — Copilot reviews op dashboard](./plans/ST-1114-copilot-reviews.md) | active | 2026-05-03 |
 | [Plan: wekelijkse sync van `model_prices` (PBI-66 / ST-1296)](./plans/sync-model-prices.md) | — | — |
 | [Tweede Claude Agent — Planning Agent](./plans/tweede-claude-agent-planning.md) | proposal | 2026-05-03 |
+| [User-settings store (DB-backed user prefs)](./plans/user-settings-store.md) | draft | 2026-05-10 |
 | [Scrum4Me — v1.0 readiness](./plans/v1-readiness.md) | active | 2026-05-04 |
 | [Zustand store rearchitecture - active context, realtime en resync](./plans/zustand-store-rearchitecture.md) | ready-to-execute | 2026-05-09 |
 | [Zustand workspace-store implementatieplan (PBI-74)](./plans/zustand-workspace-store-implementation.md) | in-progress | 2026-05-10 |