fix(CI): fix changeset reference to stale server package name blocking CI (#1801)

# why

# what changed

# test plan


<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Corrects the changeset package reference from
`@browserbasehq/stagehand-server` to
`@browserbasehq/stagehand-server-v3` to unblock CI and ensure the
correct package receives the patch release.

<sup>Written for commit 177bc48.
Summary will update on new commits. <a
href="https://cubic.dev/pr/browserbase/stagehand/pull/1801">Review in
cubic</a></sup>

<!-- End of auto-generated description by cubic. -->

Author: pirate

.changeset/add-bedrock-provider-schema.md

@@ -1,6 +1,6 @@
 ---
 "@browserbasehq/stagehand": patch
-"@browserbasehq/stagehand-server": patch
+"@browserbasehq/stagehand-server-v3": patch
 ---
 
 Add bedrock to the provider enum in model configuration schemas and regenerate OpenAPI spec.