feat(admin): add Filament resources for the forecasting stack

Adds three resources under a new "Forecasting" navigation group: a full-CRUD
WatchedEventResource for the Layer 5 volatility detector, plus read-only
WeeklyForecastResource and BacktestResource so the ridge model output and
its calibration can be inspected without SQL.

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

app/Filament/Resources/Backtests/BacktestResource.php

@@ -0,0 +1,62 @@
+<?php
+
+namespace App\Filament\Resources\Backtests;
+
+use App\Filament\NavigationGroup;
+use App\Filament\Resources\Backtests\Pages\ListBacktests;
+use App\Filament\Resources\Backtests\Pages\ViewBacktest;
+use App\Filament\Resources\Backtests\Schemas\BacktestInfolist;
+use App\Filament\Resources\Backtests\Tables\BacktestsTable;
+use App\Models\Backtest;
+use BackedEnum;
+use Filament\Resources\Resource;
+use Filament\Schemas\Schema;
+use Filament\Support\Icons\Heroicon;
+use Filament\Tables\Table;
+use Illuminate\Database\Eloquent\Model;
+
+class BacktestResource extends Resource
+{
+    protected static ?string $model = Backtest::class;
+
+    protected static string|BackedEnum|null $navigationIcon = Heroicon::OutlinedBeaker;
+
+    protected static string|\UnitEnum|null $navigationGroup = NavigationGroup::Forecasting;
+
+    protected static ?string $navigationLabel = 'Backtests';
+
+    protected static ?int $navigationSort = 3;
+
+    public static function infolist(Schema $schema): Schema
+    {
+        return BacktestInfolist::configure($schema);
+    }
+
+    public static function table(Table $table): Table
+    {
+        return BacktestsTable::configure($table);
+    }
+
+    public static function canCreate(): bool
+    {
+        return false;
+    }
+
+    public static function canEdit(Model $record): bool
+    {
+        return false;
+    }
+
+    public static function canDelete(Model $record): bool
+    {
+        return false;
+    }
+
+    public static function getPages(): array
+    {
+        return [
+            'index' => ListBacktests::route('/'),
+            'view' => ViewBacktest::route('/{record}'),
+        ];
+    }
+}