Complete networking integration gate (#58)

docs/caps-http.md

@@ -89,6 +89,10 @@ statuses and transport failures retry up to the request's configured retry
 count with bounded backoff. Disposal cancels active and queued work, wakes every
 waiter, joins the dispatcher, and prevents new requests.
 
+`DownloadManager::active_download_count`, `dispatcher_running`, and
+`is_disposed` expose payload-free lifecycle state for leak assertions. They do
+not expose capability URIs or response data.
+
 Errors expose only typed categories and `Debug` output substitutes a redacted
 marker for capability URIs. No request URL, query token, body, or response body
 is logged.

docs/network-manager.md

@@ -113,6 +113,26 @@ canceled login leaves no simulator installed. Passwords, login tokens, MFA
 hashes, session identifiers, seed capabilities, and estate access tokens are
 excluded from `Debug` output and diagnostic messages.
 
+## Statistics and milestone gate
+
+`SimulatorSimStats` is the native thread-safe counterpart of the reference
+`Simulator.SimStats`. Atomic counters track received/sent packets and bytes,
+resends, drops, pings, pongs, lag, and bandwidth samples. Server `SimStats`
+blocks update the 25 defined simulator measurements with the reference ID and
+rounding rules; unknown IDs are ignored. Debug snapshots contain aggregate
+counters only—never packet bytes, endpoints, capability URLs, or credentials.
+
+The offline fake-grid gate composes the completed layers rather than replacing
+their focused tests. It authenticates through injected LLSD HTTP, establishes a
+real loopback UDP circuit, discovers seed capabilities, consumes an
+`EventQueueGet` message that enables a second region, downloads a capability
+asset, promotes that region, and completes the logout handshake. It then proves
+CAPS polling was canceled, download and network workers were joined, sockets
+were closed, state was cleared, and diagnostic formatting contains none of the
+fixture tokens. `tools/check_milestone_08.py` also audits owned source files for
+failure-only bodies and verifies the explicit queue, payload, event, retry, and
+concurrency policy markers remain present.
+
 The deterministic tests use loopback fake simulators and require no live grid:
 
 ```sh