v0.1.9 — Finder-launch PATH hotfix

Hotfix for v0.1.8: when the .app is launched from Finder (or
open foo.app), the inherited PATH is the macOS launchd default
(/usr/bin:/bin:/usr/sbin:/sbin), which excludes Homebrew
(/opt/homebrew/bin, /usr/local/bin) and ~/bin. As a result
exec.LookPath(\"podman\") returned no match, the sandbox engine
quietly stayed nil, and the eight sandbox-* tools never showed
up — even with Settings → Sandbox turned on and an image
configured. Launching the binary directly from a terminal worked
because the shell's PATH was inherited.

Fix

A new internal/pathfix helper prepends the macOS-typical user
bin directories at main() startup, before any subprocess work
begins. Already-present and non-existent entries are skipped, so
the augmentation is idempotent and harmless on Intel macOS, on
machines that don't have Homebrew, and on systems where the user
already exported a complete PATH.

The same fix benefits any other subprocess the app shells out to
(MCP servers, gh, future tooling).

See CHANGELOG.md.

macOS-only build (Apple Silicon).