feat: keep user and workdir from the template in the sandbox

[dobrac]

Changes

• Send the default user (and workdir) with the /init call (waitForEnvd) when building a template (especially in the finalize layer)
• Update Envd
  • the user will be optional for all commands
    • when not provided, the default will be used
  • /init will receive default user (and workdir) parameters that will set global default user (and workdir)
• We still need to create user "user" during the template build for the minimum amount of breaking changes
• The sandbox user override (/init call) applies only for the v2.1.0 builds, all previous builds have always "user" as the default

Note

Adds template versioning (v1/v2) with SDK-based selection and propagates template-defined default user/workdir into sandboxes, updating envd API, build phases, and gRPC contracts accordingly.

• Template Versioning:
  • Selects template version from SDK User-Agent (JS/Python); v1 handler forces templates.TemplateV1Version.
  • Passes version through API → template-manager → orchestrator; proto gains TemplateCreateRequest.version.
  • Shared: adds templates version constants and version utils.
• Orchestrator/Builder:
  • Introduces a user phase to create/configure default user (sudo) and persist in metadata.
  • Enhances WORKDIR to resolve/normalize absolute paths and safe chowning.
  • Commands/executor accept log level; step factory sets default levels.
  • Envd init now sends default user/workdir; improved error logging on init failures.
• envd (runtime):
  • New defaults context (env vars, default user, default workdir); POST /init supports defaultUser and defaultWorkdir.
  • Username in /files is optional; auth/signing and path resolution handle missing username via defaults and workdir.
  • Filesystem/process services use defaults for user/workdir; API version bumped to 0.4.0.
• API Handlers:
  • V2 build handler derives version from User-Agent; fixes success flag; unified error handling.
• Tests/Spec:
  • OpenAPI/spec and generated clients updated (optional username, new init fields).
  • Integration tests set User-Agent, use pointer usernames, and minor command arg fixes.

^{Written by Cursor Bugbot for commit 9798fbb. This will update automatically on new commits. Configure here.}

[linear]

ENG-3049 Figure out default user (template - root, sandbox - user)

[jakubno]

NITs