Add missing license file

Author: Kyle-Ye

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025 Kyle-Ye
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -43,7 +43,8 @@ Comprehensive documentation is available on [Swift Package Index](https://swiftp
 ```swift
 import OpenObservation
 
-@Observableclass Counter {
+@Observable
+class Counter {
     var value: Int = 0
 
     func increment() {
@@ -69,4 +70,6 @@ withObservationTracking {
 ## License
 
 - **OpenObservation code**: MIT License
-- **Code derived from Swift project**: Apache License v2.0 with Runtime Library Exception
+- **Code derived from Swift project**: Apache License v2.0 with Runtime Library Exception
+
+See LICENSE file.