chore: update package versions in package.json and package-lock.json

- Bump version of @mastra/agent-browser from ^0.1.0 to ^0.2.0
- Bump version of @mastra/stagehand from ^0.1.0 to ^0.2.0
- Update project version from 1.0.43 to 1.0.44 in package.json and package-lock.json