docs: record date selection baseline

Codex Documentation/Current Software Plan/Date Selection 01 - Day Navigation and Date Picker/DATE_SELECTION_01_BLOCK_01_SCOPE_AND_BASELINE.md

@@ -4,7 +4,7 @@
 
 # Date Selection 01 Block 01 — Scope and Baseline
 
-**Status:** Planned.
+**Status:** Complete.
 **Goal:** Verify the persistence-backed app baseline and lock the exact semantics
 for date selection before implementing UI callbacks.
 
@@ -117,6 +117,33 @@ reopening architectural decisions.
 - Selected-date behavior is documented.
 - Tests and validation commands for the plan are known.
 
+## Implementation notes
+
+- Persistence Plan 1 has been fast-forward merged into `main` before this branch
+  was created. Normal Flutter startup uses `PersistentSchedulerComposition.open`
+  and `SqliteApplicationRuntime.open`; seeded demo data remains isolated to
+  `DemoSchedulerComposition.seeded` for tests and explicit demo construction.
+- The existing composition root owns `GetTodayStateQuery`,
+  `V1ApplicationCommandUseCases`, `V1ApplicationManagementUseCases`, owner id,
+  owner timezone, operation clocks, and SQLite lifecycle/disposal.
+- Selected date will live in a dedicated `SelectedDateController`. `FocusFlowHome`
+  owns that controller and wires it to Today reads and command execution. Widgets
+  will receive callbacks and display-ready labels only; they will not instantiate
+  repositories, Drift types, scheduler use cases, or engine objects.
+- Selected date is the visible owner-local `CivilDate`. Changing it is read-only:
+  previous/next move one civil day, picker selection jumps directly to the chosen
+  civil date, command timestamps use the runtime clock, backlog scheduling targets
+  the selected planning day, and completion records the real completion instant.
+- Validation targets to preserve: `scripts/test.sh`; `flutter test` in
+  `apps/focus_flow_flutter`; controller, app, widget, model, and persistent
+  lifecycle Flutter tests added by this plan; core query and command tests under
+  `packages/scheduler_core`; SQLite lifecycle tests under
+  `packages/scheduler_persistence_sqlite`.
+- Baseline validation on this branch: `flutter test` in
+  `apps/focus_flow_flutter` passed with 24 tests. `scripts/test.sh` did not reach
+  package tests because `dart analyze` failed in the Dart analysis server with
+  `OS Error: Too many open files, errno = 24` while setting analysis roots.
+
 ## Validation after block
 
 ```sh