chore: add license and build configs

README.md

@@ -1,39 +1,16 @@
-This is a Kotlin Multiplatform project targeting Android, iOS.
+Coop is a simple, fast, and reliable nostr client for secure messaging across all platforms.
 
-* [/composeApp](./composeApp/src) is for code that will be shared across your Compose Multiplatform applications.
-  It contains several subfolders:
-  - [commonMain](./composeApp/src/commonMain/kotlin) is for code that’s common for all targets.
-  - Other folders are for Kotlin code that will be compiled for only the platform indicated in the folder name.
-    For example, if you want to use Apple’s CoreCrypto for the iOS part of your Kotlin app,
-    the [iosMain](./composeApp/src/iosMain/kotlin) folder would be the right place for such calls.
-    Similarly, if you want to edit the Desktop (JVM) specific part, the [jvmMain](./composeApp/src/jvmMain/kotlin)
-    folder is the appropriate location.
+### License
 
-* [/iosApp](./iosApp/iosApp) contains iOS applications. Even if you’re sharing your UI with Compose Multiplatform,
-  you need this entry point for your iOS app. This is also where you should add SwiftUI code for your project.
+Copyright (C) 2026 Ren Amamiya & other Coop contributors
 
-* [/shared](./shared/src) is for the code that will be shared between all targets in the project.
-  The most important subfolder is [commonMain](./shared/src/commonMain/kotlin). If preferred, you
-  can add code to the platform-specific folders here too.
+This program is free software: you can redistribute it and/or modify it under the terms of the GNU
+General Public License as published by the Free Software Foundation, either version 3 of the
+License, or (at your option) any later version.
 
-### Build and Run Android Application
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
+even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+General Public License for more details.
 
-To build and run the development version of the Android app, use the run configuration from the run widget
-in your IDE’s toolbar or build it directly from the terminal:
-- on macOS/Linux
-  ```shell
-  ./gradlew :composeApp:assembleDebug
-  ```
-- on Windows
-  ```shell
-  .\gradlew.bat :composeApp:assembleDebug
-  ```
-
-### Build and Run iOS Application
-
-To build and run the development version of the iOS app, use the run configuration from the run widget
-in your IDE’s toolbar or open the [/iosApp](./iosApp) directory in Xcode and run it from there.
-
----
-
-Learn more about [Kotlin Multiplatform](https://www.jetbrains.com/help/kotlin-multiplatform-dev/get-started.html)…
+You should have received a copy of the GNU General Public License along with this program. If not,
+see https://www.gnu.org/licenses/.