feat: add integration test framework and rack/grid command support

client/tests/test_integration.c

@@ -0,0 +1,35 @@
+#define TESTING 1
+#include "carla_host.h"
+#include <stdio.h>
+#include <assert.h>
+
+int main(void)
+{
+    printf("=== Integration test (requires JACK server) ===\n");
+
+    /* Fail if no JACK server */
+    if (carla_init_jack() != 0) {
+        fprintf(stderr, "FAIL: cannot initialise Carla/JACK – is the JACK server running?\n");
+        return 1;
+    }
+
+    /* Verify handle is now non‑NULL */
+    CarlaHostHandle h = carla_get_handle();
+    assert(h != NULL);
+
+    /* Test connection tracking without loading a real plugin.
+       carla_test_add_connection adds a fake connection entry. */
+    int ret = carla_test_add_connection(0, "test:out", "looper:in");
+    assert(ret == 0);
+    assert(carla_test_connection_count() == 1);
+
+    /* Disconnect plugin ID 0 – should clear the list */
+    ret = carla_disconnect_plugin(0);
+    assert(ret == 0);
+    assert(carla_test_connection_count() == 0);
+
+    carla_cleanup_jack();
+
+    printf("PASS: all integration tests passed (with JACK server).\n");
+    return 0;
+}