Wait for every runtime discovery hears from, and name the ones it misses

The console gathered $SRV.INFO answers for a fixed 750 ms. The laptop's
runtime (48 modules, 341 endpoints, 164 kB) answers last every time: its
answer crosses to the broker on another machine and back, a median of
365 ms on a quiet link and 813 ms in one of 25 rounds measured. When it
missed the window the console said its modules ran nowhere ("nothing in
the mesh is called slack") or only on another machine.

Discovery now asks $SRV.PING alongside $SRV.INFO and waits, past the
window and up to 5 s, for every instance that answered PING. A runtime
that never sends what it serves, or answered before and not now, is
named in every answer that might concern it instead of the module being
called missing. An answer still too large after first-line descriptions
drops them, and says so in its metadata.

mesh_runtimes reports, per runtime, its machine, how long its answer
took, its size, its modules and tools, whether it was shortened and when
it was last heard, and the runtimes and machines not heard.

node-tools/internal/console/address_test.go

@@ -36,7 +36,7 @@ func call(t *testing.T, endpoint, tool string, args map[string]any) (string, boo
 	return text(t, post(t, endpoint, string(body)))
 }
 
-// novox/hq ADR 0195: the console announces five tools, and everything the mesh answers is reached
+// novox/hq ADR 0195: the console announces six tools, and everything the mesh answers is reached
 // through them by one address per layer.
 func TestTheMeshsToolsAreFoundByAddress(t *testing.T) {
 	was := IndexKept
@@ -113,7 +113,7 @@ func TestTheMeshsToolsAreFoundByAddress(t *testing.T) {
 	defer up.Close()
 	endpoint := "http://" + up.Address + "/mcp"
 
-	// Five tools, nothing else.
+	// Six tools, nothing else.
 	listed := post(t, endpoint, `{"jsonrpc":"2.0","id":2,"method":"tools/list"}`)["result"].(map[string]any)
 	var names []string
 	for _, x := range listed["tools"].([]any) {
@@ -125,7 +125,7 @@ func TestTheMeshsToolsAreFoundByAddress(t *testing.T) {
 			}
 		}
 	}
-	if got := strings.Join(names, ","); got != "mesh_overview,mesh_machine,mesh_search,mesh_describe,mesh_call" {
+	if got := strings.Join(names, ","); got != "mesh_overview,mesh_machine,mesh_search,mesh_describe,mesh_call,mesh_runtimes" {
 		t.Errorf("announced %s", got)
 	}