Add Gateway Modbus component with configuration and bridge implementation

- Created CMakeLists.txt for the Gateway Modbus component.
- Added header file `gateway_modbus.hpp` defining configuration structures, enums, and point structures.
- Implemented the `gateway_modbus.cpp` source file containing the logic for managing Modbus points, including reading and writing operations.
- Introduced utility functions for converting configurations to and from DaliValue, and for handling Modbus space and access types.
- Established a bridge class to manage Modbus points and their interactions with the DaliBridgeEngine.

Co-authored-by: Copilot <copilot@github.com>

apps/gateway/main/Kconfig.projbuild

@@ -391,7 +391,9 @@ config GATEWAY_MODBUS_BRIDGE_SUPPORTED
     depends on GATEWAY_BRIDGE_SUPPORTED && GATEWAY_WIFI_SUPPORTED
     default y
     help
-        Enables the per-channel Modbus TCP adapter backed by DaliModbusBridge. Runtime startup still requires persisted bridge config with Modbus settings.
+        Enables the gateway-owned per-channel Modbus TCP server, generated DALI point map,
+        and provisioned model overrides. Runtime startup still requires persisted bridge
+        config with Modbus settings.
 
 config GATEWAY_START_MODBUS_BRIDGE_ENABLED
     bool "Start Modbus TCP bridge at startup"

apps/gateway/main/app_main.cpp

@@ -491,7 +491,8 @@ extern "C" void app_main(void) {
       static_cast<uint32_t>(CONFIG_GATEWAY_BRIDGE_BACNET_TASK_STACK_SIZE);
     bridge_config.bacnet_task_priority =
       static_cast<UBaseType_t>(CONFIG_GATEWAY_BRIDGE_BACNET_TASK_PRIORITY);
-    s_bridge = std::make_unique<gateway::GatewayBridgeService>(*s_dali_domain, bridge_config);
+    s_bridge = std::make_unique<gateway::GatewayBridgeService>(*s_dali_domain, *s_cache,
+                                                                bridge_config);
   }
 
   if (profile.enable_wifi || profile.enable_eth) {