feat(companion): add simulator runner project skeleton

companion/Sources/PrivateAutomation/PrivateAutomation.h

@@ -0,0 +1,35 @@
+#import <Foundation/Foundation.h>
+#import <CoreGraphics/CoreGraphics.h>
+
+// Private XCTest event-synthesis interfaces. These ship inside the testing
+// frameworks bundled with Xcode and are the only path to timestamped touch
+// events with millisecond-precision offsets. The selectors below were verified
+// present in Xcode 26's XCUIAutomation framework binary.
+
+NS_ASSUME_NONNULL_BEGIN
+
+// One pointer's path through a synthesized event. Offsets are seconds from the
+// start of the event record.
+@interface XCPointerEventPath : NSObject
+- (instancetype)initForTouchAtPoint:(CGPoint)point offset:(double)offset;
+- (void)moveToPoint:(CGPoint)point atOffset:(double)offset;
+- (void)pressDownAtOffset:(double)offset;
+- (void)liftUpAtOffset:(double)offset;
+@end
+
+// A complete synthesized event composed of one or more pointer paths.
+@interface XCSynthesizedEventRecord : NSObject
+- (instancetype)initWithName:(NSString *)name
+         interfaceOrientation:(NSInteger)interfaceOrientation;
+- (void)addPointerEventPath:(XCPointerEventPath *)pointerEventPath;
+@end
+
+// The runner-side session that delivers synthesized events to the system under
+// test.
+@interface XCTRunnerDaemonSession : NSObject
++ (instancetype)sharedSession;
+- (void)synthesizeEvent:(XCSynthesizedEventRecord *)eventRecord
+             completion:(void (^)(NSError *_Nullable error))completion;
+@end
+
+NS_ASSUME_NONNULL_END