Infra/Confidence: Bundling

# TLDR

While testing windows (and while watching our unit tests) we've seen bad performance issues while installing and running gemini CLI on windows.

This PR was an exploratory spike on how to start shipping our bundled code instead of raw source. https://github.com/google-gemini/gemini-cli/pull/10023

This card is to tun that work into shippable change within our code base.

## Dive Deeper

This has several solidifying benefits.

1. makes windows installs significantly faster
2. locks down our supply chain so users don't get a hacked verion of a dependency (this has already happened)
3. I also believe it will speed up CI; if we do bundle as a shared step in CI and E2E then we can run tests against that bundle and all of the "waiting for build and npm install time - which is like > 50% of the windows test time.

I already published this once by hand: you can test the output here: `npm install -g @google/gemini-cli@0.0.44-beta.0`

## Exit Criteria
- [ ] the bundle code step is integrated into our local build scripts
- [ ] our 'publish-release' step uses the bundled code to do actual releases
- [ ] we've tested across platforms for regressions in behavior in bundled.