Refactor Lambda workflows: extract filesystem step, improve error handling

[Copilot]

Summary

• Addresses PR review feedback: extracts filesystem creation into dedicated step, enhances API error reporting, fixes deletion message timing

Changes

• deploy-lambda.yml: Split "Launch instance" into "Create or select filesystem" (new) + "Launch instance" (refactored)
  • Filesystem ID now passed via step outputs: steps.filesystem.outputs.filesystem_id
  • Error handling extracts API error from .error // .errors[0].message // .message with fallback to raw response
• teardown-lambda.yml: Deletion note only shows on curl failure (|| echo)

Testing

• Not run (reason: workflow changes validated via YAML syntax check)

Review focus

• Rust runtime paths
• Helion sidecar/worker integration

Rollout / Notes

• No functional changes to deployed resources, only workflow organization and diagnostics

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.