Add MIT license and NOTICE for bundled Xray-core (MPL-2.0)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

NOTICE.md

@@ -0,0 +1,15 @@
+# Third-party components
+
+## Xray-core
+
+This project bundles an **unmodified** binary of [Xray-core](https://github.com/XTLS/Xray-core)
+(pinned version `v26.3.27`) and runs it as a separate process. Xray-core is licensed under the
+**Mozilla Public License 2.0 (MPL-2.0)**.
+
+- Xray-core source: https://github.com/XTLS/Xray-core
+- Its `LICENSE` ships inside the release archive and is extracted to
+  `%APPDATA%\ClaudeProxy\bin\LICENSE` at runtime.
+
+Bundling and invoking Xray-core as an independent executable ("mere aggregation") does not place
+this project's own code (MIT-licensed, see `LICENSE`) under the MPL. Redistribution of the Xray
+binary is permitted by MPL-2.0 provided its license text is included, which it is.