fix: resolve install binary verification, uninstall, and version prefix bugs

[khaliqgant]

Summary

• macOS Gatekeeper "Killed: 9": Strip com.apple.quarantine xattr from all downloaded binaries before verification. Added strip_quarantine() helper used at all 7 download points in install.sh, plus xattr -d in SDK's installBrokerBinary().
• Uninstall doesn't remove binaries: agent-relay uninstall now removes standalone binaries from ~/.local/bin/, the ~/.agent-relay/ directory, and runs npm uninstall -g for all three packages.
• vopenclaw-v3.1.18 404: SDK's getLatestVersionSync() now strips both openclaw- and v prefixes from GitHub release tags before constructing download URLs.
• Version shadow warning: verify_installation() now detects when an older npm-installed binary shadows the newly installed standalone binary and advises the user.

Test plan

• Run curl -fsSL .../install.sh | bash on macOS — broker binary should pass verification (no "Killed: 9")
• Run agent-relay uninstall — verify which agent-relay returns nothing afterward
• Verify SDK auto-install of broker resolves correct URL (no vopenclaw- prefix)
• Install via both npm and standalone, verify version conflict warning appears

🤖 Generated with Claude Code

---

In general, the safest fix is to avoid exec/execSync with a single shell command string when any part of that string comes from untrusted or tainted data. Instead, use execFile/execFileSync (or spawn/spawnSync) and pass arguments as an array of strings; this avoids shell parsing, redirection, and environment-variable expansion. For cases where you truly need shell features like redirection (2>/dev/null) or || true, wrap that in a small, fixed shell snippet and keep all untrusted data passed as separate arguments, or emulate the behavior in JavaScript (e.g., ignore errors instead of || true, discard stderr instead of 2>/dev/null).

Here, we only need to (a) run xattr -d com.apple.quarantine <targetPath> and ignore any errors, and (b) run codesign --force --sign - <targetPath> and ignore errors. Both can be implemented with execFileSync without any shell metacharacters, and the “ignore failure” behavior can be preserved by wrapping each call in a try/catch as already done. So the single best fix is:

• Add execFileSync to the existing import from node:child_process.
• Replace:
  • execSync(\xattr -d com.apple.quarantine "${targetPath}" 2>/dev/null || true`, ...)withexecFileSync('xattr', ['-d', 'com.apple.quarantine', targetPath], ...). The previous 2>/dev/null || true` is unnecessary because:
    • stdio: ['pipe','pipe','pipe'] already prevents stderr from cluttering the console.
    • The try/catch around the call already makes errors non-fatal.
• Replace:
  • execSync(\codesign --force --sign - "${targetPath}"`, ...)withexecFileSync('codesign', ['--force', '--sign', '-', targetPath], ...)`.

This preserves all semantics (timeout, stdio behavior, non-fatal nature of failures), removes any use of an interpolated shell command string, and thus addresses all variants of the alert at this location.