fix: review fixes for step 4a

- e2e: the heap check uses a socket slot now, so it waits for the device
  to free it, and test_every_client_reconnecting_at_once closes its
  clients before the check runs.
- Comments and docs that still named removed things (the /controller read,
  the event buffer, memStatus, SocketEmitter, ModelSnapshot).
- ESPNetwork::emitSockets is emitStatus: one socket, and it sends the status.
- Unused includes, whitespace-only lines left by the toJSON removal.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/entryPoints/Web.cpp

@@ -10,7 +10,6 @@
 #include "Somfy.h"
 #include "WResp.h"
 #include "LoopQueue.h"
-#include "ItemSnapshot.h"
 #include "SomfySnapshot.h"
 #include "Web.h"
 #include "WebRoutes.h"