seat: a push to a named machine waits for the machine's answer, so its call says how it went (issue 629)

The seat ran `push <node> --wait 0`, so a push's call ended at "sent" and nobody learned whether the machine applied it. The caller is answered before a push starts (answersFirst, issue 265), so waiting holds nobody: the call now waits up to two minutes for the machine's own report and keeps it, applied, refused with the machine's reason, or each failed resource with its error.

cmd/mesh-controller/seatverbs_test.go

@@ -164,12 +164,14 @@ func TestAVerbMissingWhatItNeedsIsRefused(t *testing.T) {
 	}
 }
 
-// A push and a build are sent, not waited for: the asker reads status, or the build's log by its
-// id, for what happened. A repository given as a forge path is said to be one (issue 176).
+// Acts do not block the call. A build is sent, not waited for: the asker reads the build's log by its id.
+// A push answers its caller before it starts (answersFirst), so a named push waits for the machine's own
+// answer without holding anybody, and the call's record says how it went (novox/hq issue 629). A
+// repository given as a forge path is said to be one (issue 176).
 func TestActsDoNotBlockTheCall(t *testing.T) {
 	argv, _ := argvFor("push", map[string]any{"node": "one", "why": "w"})
-	if strings.Join(argv, " ") != "push one --wait 0 --why w" {
-		t.Fatalf("push waits: %v", argv)
+	if strings.Join(argv, " ") != "push one --wait 2m0s --why w" || !answersFirst(argv) {
+		t.Fatalf("a named push does not wait for the machine's answer, or holds its caller: %v", argv)
 	}
 	argv, _ = argvFor("build", map[string]any{"repository": "novox/x", "path": "modules/x"})
 	if strings.Join(argv, " ") != "build novox/x --wait 0 --self --path modules/x" {