fix: set NSApplicationActivationPolicyAccessory at launch to prevent separate app appearance

The helper was appearing as a separate app in Dock/Cmd+Tab because
the activation policy was never being set. The showAsFloatingPanel()
only handled window level, not the application-level policy.

Now sets policy=1 (Accessory) as the FIRST thing in initialise(),
before any windows are created. This means:
- No Dock icon
- No Cmd+Tab entry
- No focus steal when helper launches
- GUI window floats over Ableton as a panel

Source/Helper/main.cpp

@@ -3,6 +3,11 @@
 #include <juce_gui_basics/juce_gui_basics.h>
 #include <juce_events/juce_events.h>
 
+#if JUCE_MAC
+#include <objc/objc.h>
+#include <objc/message.h>
+#endif
+
 #include "SharedAudioBuffer.h"
 #include "IPCProtocol.h"
 #include "Constants.h"
@@ -17,6 +22,16 @@ public:
 
     void initialise(const juce::String& commandLine) override
     {
+#if JUCE_MAC
+        // SET ACTIVATION POLICY BEFORE ANYTHING ELSE
+        // Policy 1 = NSApplicationActivationPolicyAccessory
+        // This prevents: Dock icon, Cmd+Tab entry, focus stealing on launch
+        id nsApp = ((id(*)(id, SEL))objc_msgSend)((id)objc_getClass("NSApplication"),
+                                                    sel_registerName("sharedApplication"));
+        ((void(*)(id, SEL, long))objc_msgSend)(nsApp,
+                                                sel_registerName("setActivationPolicy:"), 1);
+#endif
+
         auto args = juce::StringArray::fromTokens(commandLine, " ", "\"");
 
         int parentPid = 0;