feat: extended pricing breakdown on confirmation page

docs/PROJECT_OVERVIEW.md

@@ -8,7 +8,11 @@
 1. **Step 1**: Room selection and dates (`Create\Step1Controller`)
 2. **Step 2**: Participant details with card-based UI (`Create\Step2Controller`)
 3. **Step 3**: Payment method selection (`Create\Step3Controller`)
-4. **Step 4**: Final confirmation and submission to BPN API (`Create\Step4Controller`)
+4. **Step 4**: Final confirmation with comprehensive pricing breakdown and submission to BPN API (`Create\Step4Controller`)
+   - Displays complete pricing breakdown by category (rooms, services grouped by type)
+   - Shows per-participant total pricing in card headers
+   - Displays individual service prices inline with each booked service
+   - Three-level pricing transparency: aggregate, participant, and service-level
 5. **Edit Flow**: Similar card-based UI for existing bookings (`Edit\IndexController`)
 
 ### Card-Based UI Pattern (Production)
@@ -46,7 +50,12 @@
 
 ### Service Layer (`src/Service/`)
 - `BookingService` - Core booking workflow
-- `BookingPriceCalculatorService` - Real-time pricing
+- `BookingPriceCalculatorService` - Comprehensive pricing calculations
+  - `getPricingBreakdown()` - Complete pricing breakdown with rooms and services grouped by type
+  - `calculateAllParticipantIndividualPrices()` - Per-participant total pricing
+  - `calculateIndividualParticipantPrice()` - Single participant total (room + all services)
+  - `calculateServicePricing()` - Service aggregation with grouping by subtype
+  - Powers sidebar summary and Step 4 confirmation pricing display
 - `BookingFingerprintService` - Dirty state detection for edit mode
 - `TravelDataService` - API integration and caching
 - `ParticipantCardDataService` - Card display data
@@ -285,7 +294,12 @@ Edit mode session requires proper cleanup to prevent dirty state persistence:
 - `Step1Controller.php` - Room selection and dates
 - `Step2Controller.php` - Participant details with card-based UI
 - `Step3Controller.php` - Payment method selection
-- `Step4Controller.php` - Final confirmation and API submission
+- `Step4Controller.php` - Final confirmation with comprehensive pricing display and API submission
+  - Integrates `BookingPriceCalculatorService` for complete pricing breakdown
+  - Calculates per-participant individual prices via `calculateAllParticipantIndividualPrices()`
+  - Template displays three-level pricing: aggregate breakdown, per-participant totals, and inline service prices
+  - All service prices shown in blue (text-blue-700) with German formatting
+  - Zero prices hidden per project standards
 - `SuccessController.php` - Success page after booking completion
 
 **Edit Namespace** (`src/Controller/Booking/Edit/`):
@@ -312,7 +326,12 @@ Edit mode session requires proper cleanup to prevent dirty state persistence:
 - `templates/booking/create/step_1.html.twig` - Room selection
 - `templates/booking/create/step_2.html.twig` - Participant cards
 - `templates/booking/create/step_3.html.twig` - Payment method
-- `templates/booking/create/step_4.html.twig` - Confirmation
+- `templates/booking/create/step_4.html.twig` - Final confirmation with comprehensive pricing display
+  - **Aggregate pricing breakdown**: Rooms and services grouped by type with totals
+  - **Per-participant cards**: Individual total price in header, all personal details and service selections
+  - **Inline service pricing**: Each service shows price in blue (€X,XX format) next to label
+  - **Payment summary**: Selected payment method and bank details (if debit)
+  - **Confirmation checkbox**: Final acceptance before API submission
 - `templates/booking/create/success.html.twig` - Success page
 - `templates/booking/create/error.html.twig` - Error page