feat: add macOS app launcher installer

[huangrichao2020]

Features

• Add assets/install-macos-app.sh to create an OpenManus.app launcher on macOS.
• The generated app opens Terminal in the current checkout and starts OpenManus via main.py.
• Prefer the repo virtualenv (.venv/bin/python) when present, then fall back to uv run python, then python3.
• Use the existing assets/logo.jpg as the app icon when macOS icon tooling is available.
• Install to /Applications when writable, with a fallback to ~/Applications.

Feature Docs

This follows the same small macOS launcher pattern that was accepted in lsdefine/GenericAgent: lsdefine/GenericAgent#140

Influence

This gives macOS users a Spotlight / Launchpad / Finder entry point while preserving the existing terminal-based OpenManus runtime. It does not add runtime dependencies or change the default setup flow.

Result

• bash -n assets/install-macos-app.sh
• Generated AppleScript smoke-tested with osacompile
• pre-commit not run because it is not installed in this local environment

Other

The launcher embeds the checkout path at install time. If the user moves the repo later, they can rerun the installer so the app points to the new path.

[ilonae]

A feature I'd be glad about to have. Well done.