Complete networking integration gate (#58)

crates/libremetaverse/src/download_manager.rs

@@ -319,6 +319,24 @@ impl DownloadManager {
         Ok(())
     }
 
+    /// Number of URI-deduplicated downloads currently queued or executing.
+    #[must_use]
+    pub fn active_download_count(&self) -> usize {
+        mutex(&self.0.active).len()
+    }
+
+    /// Whether the dispatcher has completed its idempotent teardown.
+    #[must_use]
+    pub fn is_disposed(&self) -> bool {
+        self.0.disposed.load(Ordering::Acquire)
+    }
+
+    /// Whether a dispatcher thread is still owned by this manager.
+    #[must_use]
+    pub fn dispatcher_running(&self) -> bool {
+        mutex(&self.0.dispatcher).is_some()
+    }
+
     #[must_use]
     pub fn parallel_downloads(&self) -> i32 {
         i32::try_from(self.0.parallel_downloads.load(Ordering::Acquire)).unwrap_or(i32::MAX)