fix(app): make npm cli bin executable via shebang

[skulidropek]

TDD proof (publisher vs consumer game)

We model release as a two-player game:

• Player A (publisher): chooses package layout and CLI entrypoint bytes.
• Player B (consumer): runs docker-git via package managers (pnpm, npm, npx).

A stable outcome requires both strategies to succeed on the same tarball.

Red (failing test before fix)

bash scripts/e2e/local-package-cli.sh failed with:

• packed CLI entrypoint missing shebang: expected '#!/usr/bin/env node'
• and runtime symptom from npm users: import: not found when invoking docker-git.

Green (fix)

• add shebang to CLI entrypoint source: packages/app/src/docker-git/main.ts
• extend release e2e test to verify:
  1. packed dist/src/docker-git/main.js starts with #!/usr/bin/env node
  2. local tarball works via pnpm docker-git --help
  3. local tarball works via npm exec -- docker-git --help

Result

The same TDD test now passes end-to-end:

• bash scripts/e2e/local-package-cli.sh ✅

Verification

• pnpm --filter ./packages/app build:docker-git
• bash scripts/e2e/local-package-cli.sh
• pnpm --filter ./packages/app typecheck
• pnpm --filter ./packages/app test