feat(server): Rework transport architecture and add StreamableHttpTransport (#49)

* feat(server): Rework transport architecture and add StreamableHttpTransport

- `Server::connect()` no longer contains a processing loop.
- `TransportInterface` is updated with `setMessageHandler()` and `listen()`.
- `StdioTransport` is updated to implement the new interface.
- A new, minimal `StreamableHttpTransport` is added for stateless HTTP.

* refactor(server): use  event-driven message handling

* feat(server): Introduce a formal session management system

* fix: ensure session elements are preserved when building server (regression from #46)

* refactor: consolidate HTTP example to use shared dependencies

* feat(server): Enhance message handling with session support

- Updated `TransportInterface` to use `onMessage` for handling incoming messages with session IDs.
- Refactored `Server`, `Handler`, and transport classes to accommodate session management using `Uuid`.
- Introduced methods for creating sessions with auto-generated and specific UUIDs in `SessionFactory` and `SessionFactoryInterface`.

* feat(server): Integrate session management in message handling

- Added session support to the `Server` and `Handler` classes, allowing for session data to be managed during message processing.
- Updated `TransportInterface` to include session context in the `send` method.
- Refactored various request handlers to utilize session information, ensuring proper session handling for incoming requests.
- Introduced a file-based session store for persistent session data management

* feat: Update session builder method to use set* instead of with*

* feat: Fix test compatibility with new session management architecture

* chore: apply code style fixes

* fix: remove deprecated SSE transport and resolve PHPStan issues

examples/03-manual-registration-stdio/server.php

@@ -19,7 +19,7 @@ use Mcp\Server\Transport\StdioTransport;
 
 logger()->info('Starting MCP Manual Registration (Stdio) Server...');
 
-Server::make()
+$server = Server::make()
     ->setServerInfo('Manual Reg Server', '1.0.0')
     ->setLogger(logger())
     ->setContainer(container())
@@ -27,7 +27,12 @@ Server::make()
     ->addResource([SimpleHandlers::class, 'getAppVersion'], 'app://version', 'application_version', mimeType: 'text/plain')
     ->addPrompt([SimpleHandlers::class, 'greetingPrompt'], 'personalized_greeting')
     ->addResourceTemplate([SimpleHandlers::class, 'getItemDetails'], 'item://{itemId}/details', 'get_item_details', mimeType: 'application/json')
-    ->build()
-    ->connect(new StdioTransport(logger: logger()));
+    ->build();
+
+$transport = new StdioTransport(logger: logger());
+
+$server->connect($transport);
+
+$transport->listen();
 
 logger()->info('Server listener stopped gracefully.');