docs(05-03): complete calendar backend plan

- Create 05-03-SUMMARY.md with full execution documentation
- Update STATE.md: advance to plan 4/5, add decisions, record metrics
- Update ROADMAP.md: mark 05-03 complete, 3/5 plans done
- Update REQUIREMENTS.md: CAL-01/02/03 + DASH-05 backend complete

.planning/STATE.md

@@ -3,15 +3,15 @@ gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
 status: executing
-stopped_at: Completed 05-02-PLAN.md
-last_updated: "2026-06-24T13:02:42.630Z"
-last_activity: 2026-06-24 -- Phase 05 execution started
+stopped_at: Completed 05-03-PLAN.md
+last_updated: "2026-06-24T13:16:25Z"
+last_activity: 2026-06-24 -- Calendar backend complete
 progress:
   total_phases: 6
   completed_phases: 3
   total_plans: 21
-  completed_plans: 17
-  percent: 50
+  completed_plans: 18
+  percent: 86
 ---
 
 # Project State
@@ -26,11 +26,11 @@ See: .planning/PROJECT.md (updated 2026-06-18)
 ## Current Position
 
 Phase: 05 (dashboard-calendar) — EXECUTING
-Plan: 3 of 5
+Plan: 4 of 5
 Status: Ready to execute
-Last activity: 2026-06-24 -- Phase 05 execution started
+Last activity: 2026-06-24 -- Calendar backend complete (Plan 03)
 
-Progress: [████████░░] 81%
+Progress: [████████░░] 86%
 
 ## Performance Metrics
 
@@ -56,6 +56,7 @@ Progress: [████████░░] 81%
 | Phase 02-authentication-multi-tenancy P03 | 5min | 2 tasks | 20 files |
 | Phase 05-dashboard-calendar P01 | 14min | 4 tasks | 28 files |
 | Phase 05-dashboard-calendar P02 | 4min | 4 tasks | 16 files |
+| Phase 05-dashboard-calendar P03 | 11min | 4 tasks | 14 files |
 
 ## Accumulated Context
 
@@ -79,6 +80,10 @@ Recent decisions affecting current work:
 - [Phase ?]: react-grid-layout v2 uses dragConfig/resizeConfig instead of isDraggable/isResizable
 - [05-02]: SearchProvider defaults as constants merged with user DB rows (no seed migration)
 - [05-02]: useRef with explicit undefined initial value for React 19 strict TypeScript
+- [05-03]: DAVClient class constructor instead of createDAVClient factory (tsdav v2 type compatibility)
+- [05-03]: Dynamic imports for ews-javascript-api and @microsoft/microsoft-graph-client (lazy-load)
+- [05-03]: In-memory Map cache with 5-min TTL for calendar events (Redis not needed at current scale)
+- [05-03]: ews-javascript-api imported as any (no TypeScript definitions available)
 
 ### Pending Todos
 
@@ -98,6 +103,6 @@ Items acknowledged and carried forward from previous milestone close:
 
 ## Session Continuity
 
-Last session: 2026-06-24T12:57:00Z
-Stopped at: Completed 05-02-PLAN.md
+Last session: 2026-06-24T13:16:25Z
+Stopped at: Completed 05-03-PLAN.md
 Resume file: None