docs(01-04): complete WizardState store plan

- 01-04-SUMMARY.md: TDD reducer + Context API store complete, 8 tests green, build clean
- STATE.md: progress 100%, decisions added, session updated
- ROADMAP.md: Phase 01 all 4 plans complete

.planning/STATE.md

@@ -3,14 +3,14 @@ gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
 status: executing
-stopped_at: Completed 01-03-PLAN.md — Zod schema builder from BACKEND_REGISTRY
-last_updated: "2026-03-26T09:22:18.904Z"
+stopped_at: Completed 01-04-PLAN.md — WizardState store complete (types, reducer, context, App wiring)
+last_updated: "2026-03-26T09:26:07.358Z"
 last_activity: 2026-03-26 — Completed plan 01-02 (Backend Schema Registry)
 progress:
   total_phases: 4
-  completed_phases: 0
+  completed_phases: 1
   total_plans: 4
-  completed_plans: 3
+  completed_plans: 4
   percent: 50
 ---
 
@@ -51,6 +51,7 @@ Progress: [█████░░░░░] 50%
 
 *Updated after each plan completion*
 | Phase 01-foundation P03 | 1 | 1 tasks | 1 files |
+| Phase 01-foundation P04 | 2min | 2 tasks | 4 files |
 
 ## Accumulated Context
 
@@ -70,6 +71,9 @@ Recent decisions affecting current work:
 - [Phase 01-02]: All FieldDef.key values snake_case matching rclone config key names exactly — wrong keys would silently break generated .conf files
 - [Phase 01-foundation]: buildZodSchema loops over BACKEND_REGISTRY — field names never hardcoded in Zod schemas, registry is single source of truth for validation shape
 - [Phase 01-foundation]: BACKEND_SCHEMAS exported as const — TypeScript narrows to exact backend schema type at call sites
+- [Phase 01-foundation]: useReducer + Context API chosen over external state library — zero dependencies, sufficient for 4-step wizard
+- [Phase 01-foundation]: useWizard throws on missing provider — fail fast prevents silent undefined state propagation
+- [Phase 01-foundation]: INITIAL_STATE.deployment.scriptTargets defaults to both ['intune','rmm'] — users deselect rather than discover
 
 ### Pending Todos
 
@@ -83,6 +87,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-03-26T09:22:18.900Z
-Stopped at: Completed 01-03-PLAN.md — Zod schema builder from BACKEND_REGISTRY
+Last session: 2026-03-26T09:26:07.353Z
+Stopped at: Completed 01-04-PLAN.md — WizardState store complete (types, reducer, context, App wiring)
 Resume file: None