Enhance MTProxy checker by introducing a new -probe mode deep-strict for stricter response validation. Update README and Docker documentation to clarify probing modes, exit codes, and the new MTPROXY_TDLIB_HELPER and MTPROXY_TDLIB_TIMEOUT environment variables for external helper integration. Refactor connection handling and error reporting to improve robustness and clarity in response verification.

internal/tdlibexec/tdlibexec_test.go

@@ -0,0 +1,17 @@
+package tdlibexec
+
+import "testing"
+
+func TestParseStdout(t *testing.T) {
+	r, err := parseStdout([]byte("noise\n{\"ok\":true,\"error\":\"\",\"exit_code\":0}\n"), nil, 42)
+	if err != nil || !r.OK || r.ExitCode != 0 || r.DurationMs != 42 {
+		t.Fatalf("got %+v err=%v", r, err)
+	}
+	r2, err := parseStdout([]byte(`{"ok":false,"error":"bad","exit_code":2}`), nil, 1)
+	if err != nil || r2.OK || r2.ExitCode != 2 || r2.Error != "bad" {
+		t.Fatalf("got %+v err=%v", r2, err)
+	}
+	if _, err := parseStdout([]byte("no json"), nil, 0); err == nil {
+		t.Fatal("expected error")
+	}
+}