devbox new subcommand

[dwhswenson]

Although parts of the devbox new command got committed accidentally in other PRs, it looks like I never managed to actually get the code that did the new implementation merged in.

The idea here is to theoretically separate the new and launch subcommands. We can still create on launch, but ideally we'll refactor to reuse the new parameters first, allowing a cleaner code path.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.79%. Comparing base (a9844a3) to head (9e53fab).

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #16      +/-   ##
==========================================
+ Coverage   99.76%   99.79%   +0.03%     
==========================================
  Files          17       18       +1     
  Lines        2938     3372     +434     
==========================================
+ Hits         2931     3365     +434     
  Misses          7        7              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Copilot]

Pull request overview

This PR implements the local devbox new flow for creating a READY DevBox project record from an AMI without launching an EC2 instance, and refactors shared AMI lookup/client injection utilities used by launch, snapshot, and manager code.

Changes:

• Added devbox.new project creation implementation and tests.
• Extended the Click new command with instance/key defaults and shared param-prefix validation.
• Added utils.get_image() and refactored AMI lookups across launch, snapshots, and manager code.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/devbox/new.py	Adds standalone/programmatic project creation flow.
src/devbox/cli.py	Wires devbox new options and shared param-prefix validation.
src/devbox/utils.py	Adds injectable AWS helpers and shared AMI lookup helper.
src/devbox/launch.py	Uses shared AMI lookup for volume and SSH username handling.
src/devbox/lifecycle/snapshots.py	Uses shared AMI lookup during cleanup and mapping creation.
src/devbox/devbox_manager.py	Uses shared AMI lookup when deleting AMI snapshots.
tests/test_new.py	Adds unit coverage for new project creation and standalone entrypoint.
tests/test_cli.py	Adds CLI coverage for new and param-prefix env behavior.
tests/test_utils.py	Adds helper injection and AMI lookup tests.
tests/test_launch.py	Adds/updates launch username and missing AMI metadata tests.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.