tinygo missing vcs info

When generating a new go plugin, and then going to run `xtp plugin build`:

```
[I] ben@dylibso ~/dlete> xtp plugin build
🔨 Building dist/plugin.wasm
Running build script: mkdir -p dist && tinygo build -target wasi -o dist/plugin.wasm .
error obtaining VCS status: exit status 128
Use -buildvcs=false to disable VCS stamping.
Log file: /Users/ben/Library/Caches/xtp/xtp-1732118894-40444.log
```

`-buildvcs=false` seems to be an option on go, not tinygo. So i'm not sure how to set that. we could perhaps init a git repo in `prepare.sh`? or we can figure out how to get tinygo not to do this.

Reproduce the failure with `xtp plugin build` on a newly generated Go plugin, then inspect the generated build flow and the `prepare.sh` script proposed in the report. Confirm how TinyGo invokes VCS stamping; done means the plugin builds to `dist/plugin.wasm` without the VCS-status error.

Written by the indexing model from the issue text.