Add public domain license and copyright headers

- Added LICENSE file with Unlicense (public domain dedication)
- Added public domain headers to all main source files
- Updated README to mention public domain status
- All code is free and unencumbered, released into the public domain

Anyone is free to use this code for any purpose without restriction.

LICENSE

@@ -0,0 +1,24 @@
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
+
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
+
+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 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.
+
+For more information, please refer to <https://unlicense.org>

README.md

@@ -2,6 +2,10 @@
 
 A secure, end-to-end encrypted Bluetooth mesh chat application with an IRC-style interface.
 
+## License
+
+This project is released into the public domain. See the [LICENSE](LICENSE) file for details.
+
 ## Features
 
 - End-to-end encryption using Curve25519 and AES-GCM

bitchat/BitchatApp.swift

@@ -1,3 +1,11 @@
+//
+// BitchatApp.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import SwiftUI
 import UserNotifications
 

bitchat/Protocols/BinaryProtocol.swift

@@ -1,3 +1,11 @@
+//
+// BinaryProtocol.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import Foundation
 
 extension Data {

bitchat/Protocols/BitchatProtocol.swift

@@ -1,3 +1,11 @@
+//
+// BitchatProtocol.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import Foundation
 import CryptoKit
 

bitchat/Services/BluetoothMeshService.swift

@@ -1,3 +1,11 @@
+//
+// BluetoothMeshService.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import Foundation
 import CoreBluetooth
 import Combine

bitchat/Services/EncryptionService.swift

@@ -1,3 +1,11 @@
+//
+// EncryptionService.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import Foundation
 import CryptoKit
 

bitchat/ViewModels/ChatViewModel.swift

@@ -1,3 +1,11 @@
+//
+// ChatViewModel.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import Foundation
 import SwiftUI
 import Combine

bitchat/Views/ContentView.swift

@@ -1,3 +1,11 @@
+//
+// ContentView.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
 import SwiftUI
 
 struct ContentView: View {