Fix accidental VMApp removal when extension update fails. Also migrate VMApp download directory on extension update.

[D1v38om83r]

Summary

• removed the "uninstall all VMApp behavior" or VMApp extension uninstall
• made the extension update callback method more robust
  • previously, it searched for its own extension version in the configuration folder path, now it uses a version pattern
• added additional behavior to also copy the download directory and all its subfolders to the download directory of the new extension version
• update the package registry file with the new download directory path
• made the extension version a mandatory parameter for both MAKEFILE and makefile.win, this will ensure that the correct value for compile time variable ExtensionVersion is set when it is published

Changes

• main/main.go

  • Removed vmAppUninstallCallback and doVmAppUninstallCallback functions
  • Set ii.UninstallCallback = nil — no special handling needed on uninstall

• main/main_test.go

  • Removed 4 uninstall tests

• main/update_windows.go

  • ModifiedfindVersionDir to walk up the directory tree using filepath.Dir root detection instead of a magic-number loop limit
  • Replaced strings.Contains(name, ExtensionVersion) with regex-based utils.IsValidVersionString for version directory detection
  • Added moveDownloadDirToCurrentVersion — copies download subdirectories from older versions to the current version using robocopy
  • Added updateDonwnloadDirInPackageRegistryFile — uses regex replacement to update the extension version segment in each package's DownloadDir path
  • Added copySubdirectoryUsingRobocopy — wrapper around robocopy with proper exit code handling
  • Both new operations are best-effort with warning-level logging on failure

• pkg/utils/versionstringutils.go

  • Added IsValidVersionString function using regex ^[0-9]+(\.[0-9]+){2,4}$
  • Updated versionStringPattern to require at least 3 version segments

• main/update_windows_test.go

  • Added 9 new tests covering download directory migration, registry path updates, edge cases (no packages, no older versions, non-version directories), and a full end-to-end test