chore: remove the TypeScript code from the repository (#2048)

This deletes the bulk of the `codex-cli` folder and eliminates the logic
that builds the TypeScript code and bundles it into the release.

Since this PR modifies `.github/workflows/rust-release.yml`, to test
changes to the release process, I locally commented out all of the "is
this commit on upstream `main`" checks in
`scripts/create_github_release.sh` and ran:

```
./codex-rs/scripts/create_github_release.sh 0.20.0-alpha.4
```

Which kicked off:

https://github.com/openai/codex/actions/runs/16842085113

And the release artifacts appear legit!

https://github.com/openai/codex/releases/tag/rust-v0.20.0-alpha.4

pnpm-workspace.yaml

@@ -1,10 +1,5 @@
 packages:
-  - codex-cli
   - docs
-  - packages/*
 
 ignoredBuiltDependencies:
   - esbuild
-
-patchedDependencies:
-  marked-terminal@7.3.0: patches/marked-terminal@7.3.0.patch