## v0.25.2

Patch release fixing a latent binary auto-download bug that has affected anyone whose npm optional-dependencies didn't install — most commonly Windows users hitting `bun add`'s known reliability issues with optional deps.

## What was broken

When the resolver fell through to the GitHub Releases auto-download fallback (because the bundled `@cortexkit/aft-<platform>` package was missing or version-mismatched), it constructed a 404 URL: `releases/download/0.25.1/aft-darwin-arm64` — missing the `v` prefix that GitHub release tags actually use. Users in that path saw repeated:

```
ERROR [aft-plugin] Failed to download AFT binary: HTTP 404: Not Found
```

This is almost certainly the same root cause as [issue #39](https://github.com/cortexkit/aft/issues/39), where a Windows user had to manually place files in the binary cache to recover.

## Why this stayed hidden

The auto-download path is the last resort in the resolver. Most users get the binary directly from the npm platform package they install alongside `@cortexkit/aft-opencode`. The hot-swap upgrade path (which prepends `v` explicitly) also worked correctly, so all our local upgrade testing passed. Only the "platform package didn't install or doesn't match" first-install case was broken.

## What changed

`downloadBinary(version)` and `ensureBinary(version)` now normalize the tag to a `v`-prefixed form internally. Both `"v0.25.1"` and `"0.25.1"` produce the same correct URL + cache directory. Three regression tests pin this behavior.

If you've been seeing `HTTP 404` in `$TMPDIR/aft-plugin.log`, upgrading to 0.25.2 fixes it.
