build: add chocolatey package, remove legacy dist build scripts

The old manual dist/build/* scripts and dist/{deb,rpm}.sh are superseded by the
automated release workflow. Add the chocolatey package consumed by release.yml.

dist/chocolatey/tools/chocolateyinstall.ps1

@@ -0,0 +1,25 @@
+$ErrorActionPreference = 'Stop';
+$toolsDir = "$(Split-Path -parent $MyInvocation.MyCommand.Definition)"
+
+# Detect arch: PROCESSOR_ARCHITECTURE is "ARM64" on ARM, "AMD64" on x64
+$is_arm64 = $env:PROCESSOR_ARCHITECTURE -eq 'ARM64' -or $env:PROCESSOR_ARCHITEW6432 -eq 'ARM64'
+
+if ($is_arm64) {
+    $url      = 'https://github.com/veeso/termscp/releases/download/v1.0.0/termscp-v1.0.0-msvc.zip'
+    $checksum = 'f6ad6c62f1578562f9af4bcee93bd4cc429cb52219c3636359b008db8789587e'
+} else {
+    $url      = 'https://github.com/veeso/termscp/releases/download/v1.0.0/termscp-v1.0.0-x86_64-pc-windows-msvc.zip'
+    $checksum = 'd7796081b6f67b82acfa94557aa6852d12a33daab3cca6490660b20e42752005'
+}
+
+$packageArgs = @{
+    packageName    = $env:ChocolateyPackageName
+    fileType       = 'EXE'
+    url            = $url
+    unzipLocation  = $toolsDir
+    softwareName   = 'termscp*'
+    checksum       = $checksum
+    checksumType   = 'sha256'
+    validExitCodes = @(0, 3010, 1641)
+}
+Install-ChocolateyZipPackage @packageArgs