build: remove support for swift[<6.2]

Raise the minimum macOS release to macOS 26 and bump to Swift 6.2. This
matches the requirements for swift-platform-core which eases the use of
VirtualTerminal in other projects.

Author: compnerd

.github/workflows/build.yml

@@ -11,18 +11,18 @@ jobs:
       matrix:
         include:
           - os: ubuntu-latest
-            swift-version: swift-6.1.2-release
-            swift-build: 6.1.2-RELEASE
+            swift-version: swift-6.2-release
+            swift-build: 6.2-RELEASE
             build-args: "--traits GNU"
 
           - os: macos-latest
-            swift-version: swift-6.1.2-release
-            swift-build: 6.1.2-RELEASE
+            swift-version: swift-6.2-release
+            swift-build: 6.2-RELEASE
             build-args: ""
 
           - os: windows-latest
-            swift-version: swift-6.1.2-release
-            swift-build: 6.1.2-RELEASE
+            swift-version: swift-6.2-release
+            swift-build: 6.2-RELEASE
             build-args: ""
 
     runs-on: ${{ matrix.os }}

Package.swift

@@ -5,7 +5,7 @@ import PackageDescription
 let _: Package =
   .init(name: "VirtualTerminal",
         platforms: [
-          .macOS(.v15),
+          .macOS(.v26),
         ],
         products: [
           .executable(name: "VTDemo", targets: ["VTDemo"]),