feat(brain): add single-stream visual prototype (T-017)

Brain/yovision_brain/__main__.py

@@ -0,0 +1,47 @@
+from __future__ import annotations
+
+import argparse
+import sys
+
+from .runtime import DemoEngine
+from .server import parse_bind, serve
+from .source import StreamSource, SyntheticSource, read_stream_url, require_opencv
+
+
+def build_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser(description="YoVision Brain single-stream engineering prototype")
+    parser.add_argument("--source", choices=("synthetic", "stream"), default="synthetic")
+    parser.add_argument("--stream-url-file", help="absolute external file containing one RTSP URL")
+    parser.add_argument("--bind", default="127.0.0.1:8090", help="loopback bind address")
+    parser.add_argument("--fps", type=float, default=2.0, help="prototype processing FPS (0, 30]")
+    return parser
+
+
+def main(argv: list[str] | None = None) -> int:
+    args = build_parser().parse_args(argv)
+    try:
+        require_opencv()
+        parse_bind(args.bind)
+        if args.source == "stream":
+            if not args.stream_url_file:
+                raise ValueError("--stream-url-file is required for stream mode")
+            source = StreamSource(read_stream_url(args.stream_url_file))
+        else:
+            if args.stream_url_file:
+                raise ValueError("--stream-url-file is only valid for stream mode")
+            source = SyntheticSource()
+        engine = DemoEngine(source, fps=args.fps)
+    except (RuntimeError, ValueError) as exc:
+        print(f"Brain demo configuration error: {exc}", file=sys.stderr)
+        return 2
+    print(f"Brain demo listening on http://{args.bind}/brain-demo")
+    print("Engineering prototype only; synthetic replay and HOG output are not production model evidence.")
+    try:
+        serve(engine, args.bind)
+    except KeyboardInterrupt:
+        return 0
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())