macOS native installs can be set up as a signed claude.app bundle

The native installer, which downloads and updates Claude Code itself, can now install it on macOS as a claude.app app bundle (the folder format macOS uses for applications) instead of a single plain program file. Before, it only downloaded the plain program and checked its checksum (a fingerprint that confirms the file arrived intact).

In bundle mode it downloads the bundle, checks its checksum, unpacks it, checks its app information file, confirms its code signature with macOS, does a trial run, and then points the installed version at it. The signed list of available versions can now name a bundle for each platform.

It is tried only when all of these hold:

• you are on macOS
• you use Anthropic directly rather than a third-party provider
• it is a normal release build, not a development build
• the folder that holds installed versions belongs to your user account
• CLAUDE_CODE_NATIVE_APP_BUNDLE is set, or, when it is not set, a remote switch allows it (off unless it is switched on remotely)

If any step fails, or the version list does not pass every check, Claude Code installs the plain program instead and says so. Claude Code also records how each bundle install went and how long it took.