feat(08-10-receipt-module): phases 08-10 complete — receipt issuing from orders

Phase 08 — DB Foundation:
- 3 new tables: receipt_configs, receipts, receipt_number_counters
- company_settings extended with BDO, REGON, KRS, logo fields

Phase 09 — Receipt Config:
- CRUD for receipt configurations (Settings > Accounting)
- ReceiptConfigController + ReceiptConfigRepository

Phase 10 — Receipt Issuing:
- ReceiptRepository with atomic numbering (INSERT ON DUPLICATE KEY UPDATE)
- ReceiptController with snapshot pattern (seller/buyer/items as JSON)
- "Wystaw paragon" button in order view
- Documents tab showing both receipts and marketplace documents
- Activity log entry on receipt creation

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

database/migrations/20260315_000051_create_receipts_table.sql

@@ -0,0 +1,23 @@
+CREATE TABLE IF NOT EXISTS `receipts` (
+  `id` INT UNSIGNED NOT NULL AUTO_INCREMENT,
+  `order_id` BIGINT UNSIGNED NOT NULL,
+  `config_id` INT UNSIGNED NOT NULL,
+  `receipt_number` VARCHAR(64) NOT NULL,
+  `issue_date` DATE NOT NULL,
+  `sale_date` DATE NOT NULL,
+  `seller_data_json` JSON NOT NULL,
+  `buyer_data_json` JSON DEFAULT NULL,
+  `items_json` JSON NOT NULL,
+  `total_net` DECIMAL(12,2) NOT NULL DEFAULT 0.00,
+  `total_gross` DECIMAL(12,2) NOT NULL DEFAULT 0.00,
+  `order_reference_value` VARCHAR(128) DEFAULT NULL,
+  `created_by` INT UNSIGNED DEFAULT NULL,
+  `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY (`id`),
+  UNIQUE KEY `receipts_number_unique` (`receipt_number`),
+  KEY `receipts_order_idx` (`order_id`),
+  KEY `receipts_config_idx` (`config_id`),
+  KEY `receipts_issue_date_idx` (`issue_date`),
+  CONSTRAINT `receipts_order_fk` FOREIGN KEY (`order_id`) REFERENCES `orders` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT `receipts_config_fk` FOREIGN KEY (`config_id`) REFERENCES `receipt_configs` (`id`) ON DELETE RESTRICT ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;