feat(keyboard): improve typing, voice flow, and polish reliability

Reduce extension memory pressure and delivery races while adding richer candidates, tactile feedback, and safer two-level creative polishing.

OSGKeyboardExt/BootProbe.m

@@ -0,0 +1,15 @@
+// BootProbe.m
+// OSGKeyboard · Keyboard Extension
+//
+// Runs at dyld load — before any Swift `KeyboardViewController` init.
+// If Console shows this line but never `KVC.init`, Swift/Shared init is the
+// killer. If even this line is missing, the extension was jetsammed during
+// dyld (usually host coexistence or an oversized Shared+Rime mapping).
+
+#import <Foundation/Foundation.h>
+#include <unistd.h>
+
+__attribute__((constructor))
+static void OSGKeyboardExtBootProbe(void) {
+    NSLog(@"[OSGDiag/boot] dyld.constructor pid=%d", getpid());
+}