refactor: reorganize project structure with modern C++ namespace organization

- Restructure include/ and src/ directories with logical grouping
- Move core components to spore/core/ (NodeContext, NetworkManager, TaskManager, ClusterManager, ApiServer)
- Move services to spore/services/ (NodeService, NetworkService, ClusterService, TaskService)
- Move types to spore/types/ (NodeInfo, ApiTypes, Config)
- Move internal components to spore/internal/ (Globals)
- Update all #include statements to use new namespace paths
- Update platformio.ini build filters for all environments
- Update all example files to use new include paths
- Maintain backward compatibility for public API
- Improve code organization, maintainability, and scalability

This reorganization follows modern C++ project structure patterns and provides
clear separation between public API, internal implementation, and utilities.
All examples compile successfully with the new structure.

include/spore/core/ApiServer.h

@@ -0,0 +1,48 @@
+#pragma once
+#include <Arduino.h>
+#include <ArduinoJson.h>
+#include <ESPAsyncWebServer.h>
+#include <Updater.h>
+#include <functional>
+#include <vector>
+#include <tuple>
+
+#include "spore/core/NodeContext.h"
+#include "spore/types/NodeInfo.h"
+#include "spore/core/TaskManager.h"
+#include "spore/types/ApiTypes.h"
+
+class Service;  // Forward declaration
+
+class ApiServer {
+public:
+    ApiServer(NodeContext& ctx, TaskManager& taskMgr, uint16_t port = 80);
+    void begin();
+    void addService(Service& service);
+    void addEndpoint(const String& uri, int method, std::function<void(AsyncWebServerRequest*)> requestHandler);
+    void addEndpoint(const String& uri, int method, std::function<void(AsyncWebServerRequest*)> requestHandler,
+                    std::function<void(AsyncWebServerRequest*, const String&, size_t, uint8_t*, size_t, bool)> uploadHandler);
+
+    void addEndpoint(const String& uri, int method, std::function<void(AsyncWebServerRequest*)> requestHandler,
+                    const std::vector<ParamSpec>& params);
+    void addEndpoint(const String& uri, int method, std::function<void(AsyncWebServerRequest*)> requestHandler,
+                    std::function<void(AsyncWebServerRequest*, const String&, size_t, uint8_t*, size_t, bool)> uploadHandler,
+                    const std::vector<ParamSpec>& params);
+
+    static const char* methodToStr(int method);
+    
+    // Access to endpoints for endpoints endpoint
+    const std::vector<EndpointInfo>& getEndpoints() const { return endpoints; }
+
+private:
+    AsyncWebServer server;
+    NodeContext& ctx;
+    TaskManager& taskManager;
+    std::vector<std::reference_wrapper<Service>> services;
+    std::vector<EndpointInfo> endpoints;  // Single source of truth for endpoints
+
+    // Internal helpers
+    void registerEndpoint(const String& uri, int method, 
+                         const std::vector<ParamSpec>& params,
+                         const String& serviceName);
+};