WIP(initial-implementation): parallel batch P2/P3/P5 — code complete, unreviewed

Snapshot of the parallel batch (Phases 2 + 3 + 5) at session pause. Solution does
NOT build cleanly yet — known cross-phase compile issues remain to be resolved
before review. See plans/initial-implementation/PLAN.md "Resume Notes" section
for the exact tomorrow-morning action list.

Phase 2 (Storage):
- Repository interfaces in Marathon.Application/Abstractions
- DateRange, ExportKind, StorageOptions in Marathon.Application/Storage
- EF Core 8 + SQLite (WAL) persistence: 7 entities + configurations + 4 repos
- Hand-written InitialCreate migration (dotnet ef blocked by parallel work)
- ClosedXML ExcelExporter with exact customer-spec wide columns
- PersistenceModule.AddMarathonPersistence DI extension
- Round-trip + export tests (cannot run yet — see cross-phase issues)

Phase 3 (Scraping):
- IOddsScraper, IBetPlacer in Marathon.Application/Abstractions
- ScrapingOptions in Marathon.Infrastructure/Configuration
- MarathonbetScraper with 4 parsers (Upcoming, Live, EventOdds, Results)
- Helpers: ServerTimeProvider, PeriodScopeMapper, OutcomeCodeMapper, MoscowDateParser
- UserAgentRotatorHandler + Polly v8 resilience pipeline
- ScrapingModule.AddMarathonScraping DI extension
- GlobalUsings.cs aliases for EventId / Configuration disambiguation
- Parser tests with trimmed HTML fixtures
- ScrapeResultsAsync interim no-op (Phase 8 will replace via watch-list polling)

Phase 5 (UI shell — killed mid-final-verify, assumed ~95%):
- Marathon.UI populated: MainLayout, App.razor, Pages (Home, Settings),
  Components, Theme (MarathonTheme.cs + Tokens.cs + app.css), Resources
  (SharedResource.{cs,ru.resx,en.resx}), Services (ISettingsWriter), wwwroot
- WPF host: App.xaml(.cs), MainWindow.xaml(.cs), Marathon.Hosts.WpfBlazor.csproj
  with Microsoft.AspNetCore.Components.WebView.Wpf + MudBlazor + Serilog
- appsettings.json + appsettings.Development.json with all sections wired
- bUnit tests: MainLayoutTests, LocaleSwitcherTests, ThemeToggleTests,
  JsonSettingsWriterTests + Support helpers

Cross-phase issues to resolve at next session:
1. Phase 2 repository classes are 'internal' — Phase 3's tests can't reference
   them. Fix: add InternalsVisibleTo to Marathon.Infrastructure.csproj.
2. Phase 5: LocalizationOptions namespace ambiguity (AspNetCore vs Extensions).
3. Phase 5: WpfBlazor Serilog API mismatch.

Reviewer has NOT run on this batch. Move to Phase 4 only after build is green
and a combined parallel-batch reviewer passes.

src/Marathon.UI/MainLayout.razor

@@ -0,0 +1,119 @@
+@inherits LayoutComponentBase
+@inject ThemeState ThemeState
+@inject LocaleState LocaleState
+@inject IStringLocalizer<SharedResource> L
+
+<MudThemeProvider IsDarkMode="@ThemeState.IsDark" Theme="@_theme" />
+<MudPopoverProvider />
+<MudDialogProvider FullWidth="true" MaxWidth="MaxWidth.Small" CloseOnEscapeKey="true" />
+<MudSnackbarProvider />
+
+<div class="m-app-frame @(_drawerOpen ? "is-drawer-open" : null)" data-theme="@(ThemeState.IsDark ? "dark" : "light")">
+
+    <header class="m-appbar">
+        <MudIconButton
+            Icon="@Icons.Material.Outlined.Menu"
+            Color="Color.Inherit"
+            Edge="Edge.Start"
+            OnClick="ToggleDrawer"
+            aria-label="@L["Nav.Section.Analysis"]" />
+
+        <AppBrand Class="m-rise m-rise-1" />
+
+        <div class="m-appbar__spacer"></div>
+
+        <div class="m-appbar__tools m-rise m-rise-2">
+            <LocaleSwitcher />
+            <ThemeToggle />
+        </div>
+    </header>
+
+    <MudDrawer
+        @bind-Open="_drawerOpen"
+        Anchor="Anchor.Left"
+        Variant="DrawerVariant.Responsive"
+        ClipMode="DrawerClipMode.Always"
+        Elevation="0"
+        Width="248px"
+        Color="Color.Dark">
+        <NavBody />
+    </MudDrawer>
+
+    <main class="m-main">
+        <CascadingValue Value="ThemeState">
+            <CascadingValue Value="LocaleState">
+                @Body
+            </CascadingValue>
+        </CascadingValue>
+    </main>
+
+    <footer class="m-footer">
+        <span class="m-kicker">Marathon Odds Lab</span>
+        <span style="font-family: var(--m-font-mono); font-size: 0.6875rem; color: var(--m-c-ink-soft); letter-spacing: 0.16em; text-transform: uppercase;">
+            Phase 5 · Editorial-Quant · v0.1
+        </span>
+    </footer>
+</div>
+
+<style>
+    .m-app-frame {
+        display: grid;
+        grid-template-rows: 60px 1fr 36px;
+        min-height: 100vh;
+    }
+
+    .m-appbar {
+        display: flex;
+        align-items: center;
+        gap: var(--m-space-3);
+        padding: 0 clamp(var(--m-space-3), 2vw, var(--m-space-5));
+        border-bottom: 1px solid var(--m-c-rule);
+        background: var(--m-c-paper);
+        position: sticky;
+        top: 0;
+        z-index: 10;
+    }
+
+    .m-appbar__spacer { flex: 1; }
+    .m-appbar__tools { display: inline-flex; gap: var(--m-space-3); align-items: center; }
+
+    .m-main {
+        position: relative;
+        z-index: 1;
+        min-height: 0;
+    }
+
+    .m-footer {
+        display: flex;
+        align-items: center;
+        justify-content: space-between;
+        padding: 0 clamp(var(--m-space-3), 2vw, var(--m-space-5));
+        border-top: 1px solid var(--m-c-rule);
+        background: var(--m-c-paper);
+    }
+
+    [data-theme="dark"] .m-appbar,
+    [data-theme="dark"] .m-footer {
+        background: var(--m-c-paper-2);
+        border-color: var(--m-c-rule);
+    }
+</style>
+
+@code {
+    private bool _drawerOpen = true;
+    private MudBlazor.MudTheme _theme = Theme.MarathonTheme.Build();
+
+    protected override void OnInitialized()
+    {
+        ThemeState.OnChange += StateHasChanged;
+        LocaleState.OnChange += StateHasChanged;
+    }
+
+    private void ToggleDrawer() => _drawerOpen = !_drawerOpen;
+
+    public void Dispose()
+    {
+        ThemeState.OnChange -= StateHasChanged;
+        LocaleState.OnChange -= StateHasChanged;
+    }
+}