Use the Windows installer for Warp Agent CLI autoupdates (#14477)

## Description
Make Windows Warp Agent CLI background updates download and execute the
same signed Inno installer used for initial installation.

Windows no longer parses or installs ZIP payloads in Rust. The updater
verifies the installer with `WinVerifyTrust`, invokes it silently
against the detected managed root, verifies the completed version and
active pointer, and then performs conservative lease-aware cleanup. Unix
tarball updates, polling, status, telemetry, custom-root detection, and
live-version leases are unchanged.

Artifact publication remains intentionally disabled. This replaces
reference PR #14446 without modifying it.

Depends on #14476 and warpdotdev/warp-server#13497.

Implementation plan:
https://staging.warp.dev/drive/notebook/BI2TyxneCNDssiTUVIF0iK

## Linked Issue
- [ ] The linked issue is labeled `ready-to-spec` or
`ready-to-implement`.
- [ ] Where appropriate, screenshots or a short video of the
implementation are included below.

## Testing
- `./script/format`
- Repository-prescribed split Clippy checks
- `cargo test -p warp_tui --lib autoupdate --features
release_bundle,standalone,crash_reporting` — 17 passed
- Windows tests retain Authenticode rejection, installed-payload
validation, custom-root arguments, current/previous behavior, rollback
retention, and live-version garbage collection
- Native Windows and cross-repository release validation will be linked
after the remote branches are exercised

- [ ] I have manually tested my changes locally with `./script/run`

## Agent Mode
- [x] Warp Agent Mode - This PR was created via Warp's AI Agent Mode

CHANGELOG-NONE

Co-Authored-By: Warp <agent@warp.dev>

Co-authored-by: Warp <agent@warp.dev>

Author: kevinyang372