fix(cli): resolve runner from prebuilt installs

[pgherveou]

Summary

• resolve the packaged product-script runner through the installer's PATH and current symlinks
• keep a running binary paired with its matching runner if a background update moves current
• exercise a real product script through the installed entrypoint in the release E2E

Root cause

The release archive contained runner.js, but macOS reported the symlink used to launch truapi-host. Runner lookup checked beside that PATH entry, found no bundle, and fell back to the GitHub Actions build path compiled through CARGO_MANIFEST_DIR.

Verification

• make e2e-cli-update
• cargo test -p truapi-host-cli script_runner::tests
• cargo test --workspace --all-features --all-targets
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo build --workspace
• npm run test:scripts
• cargo +nightly fmt --all -- --check
• npx prettier --check scripts/e2e-cli-update.mjs

Created with assistance from OpenAI Codex.