feat(110): statistics summary

Phase 110 complete:
- add Statistics -> Podsumowanie page
- add monthly order count and value charts per integration plus total
- use Chart.js with table fallback and 04-2026 default history start
- update PAUL and DOCS technical documentation

.paul/codebase/architecture.md

@@ -42,7 +42,7 @@ HTTP Request
 | **Settings** | 51+ | Integration controllers, OAuth clients, API clients, mappers | Allegro/shopPRO/Apaczka/InPost config, status mappings |
 | **Cron** | 12 | `CronRepository`, `CronHandlerFactory`, handler classes | Scheduled imports, syncs, token refresh |
 | **Printing** | 4 | `PrintApiController`, `PrintJobRepository`, `ApiKeyMiddleware` | REST API for Windows print client |
-| **Statistics** | 2 | `OrdersStatisticsController`, `OrdersStatisticsRepository` | Dashboard aggregates |
+| **Statistics** | 3 | `OrdersStatisticsController`, `OrdersStatisticsRepository`, `statistics-summary-charts.js` | Daily order statistics and monthly summary charts |
 | **Info** | 1 | `InfoController` | Health check |
 
 ## Frontend Enhancement Modules
@@ -51,9 +51,16 @@ HTTP Request
 - Loaded globally from `resources/views/layouts/app.php`.
 - Enhances native `<select multiple data-checkbox-multiselect>` controls after `DOMContentLoaded`.
 - Keeps the original select in the form, synchronizes option `selected` state, and preserves native GET/POST names such as `channels[]` and `status_groups[]`.
-- Used by `/statistics/orders` filters to display a compact trigger, checkbox dropdown, "Wszystkie" bulk toggle, and selected count.
+- Used by `/statistics/orders` and `/statistics/summary` filters to display a compact trigger, checkbox dropdown, "Wszystkie" bulk toggle, and selected count.
 - Progressive enhancement: if JavaScript fails, the native multi-select remains visible.
 
+### Statistics Summary Charts (`public/assets/js/modules/statistics-summary-charts.js`)
+- Loaded globally from `resources/views/layouts/app.php` after Chart.js 4.4.8 CDN; activates only when `#js-statistics-summary-data` exists.
+- Reads JSON produced by `OrdersStatisticsController::summary()` and renders two interactive Chart.js line charts on `/statistics/summary`.
+- Chart 1 displays monthly order counts per selected integration plus a `Razem` line.
+- Chart 2 displays monthly gross order values per selected integration plus a `Razem` line.
+- The PHP view keeps table fallbacks under both charts, so the data remains visible if JavaScript fails.
+
 ## Key Data Flows
 
 ### Order Lifecycle
@@ -61,6 +68,13 @@ HTTP Request
 2. **Status update** — `OrdersController::updateStatus()` → `OrdersRepository::updateStatus()` → automation check
 3. **Status sync** — Cron → `AllegroStatusSyncService` / `ShopproStatusSyncService` → carrier API
 
+### Statistics Summary
+1. **Request** — `/statistics/summary` → `OrdersStatisticsController::summary()`
+2. **Filters** — controller reuses statistics filter semantics: date range, `channels[]`, `status_groups[]`, default status groups excluding cancelled; default history starts at `2026-04-01`.
+3. **Aggregation** — `OrdersStatisticsRepository::aggregateByMonth()` groups existing `orders` rows by `YYYY-MM` and channel key, using the same effective date/channel/status/gross amount SQL helpers as the daily report.
+4. **View model** — controller builds per-integration series and total series for order count and gross value charts.
+5. **Render** — `resources/views/statistics/summary.php` renders filters, chart JSON, two canvas targets, and table fallbacks.
+
 ### Shipment Flow
 1. **Create** — `ShipmentController::create()` → `ShipmentProviderRegistry` → carrier `ShipmentService::createShipment()` → `ShipmentPackageRepository::insert()`
 2. **Track** — Cron `ShipmentTrackingHandler` → `ShipmentTrackingRegistry` → carrier tracking API → `ShipmentPackageRepository::updateDeliveryStatus()`