Fix name-only canonical inference for project/env create

[fhacloid]

Summary

• allow project create to work with --name only by inferring canonical via NameOrCanonical
• apply the same name/canonical inference to env create
• add optional cyargs getters (GetProjectOrEmpty, GetEnvOrEmpty) for create flows that accept either name or canonical
• harden NameOrCanonical so empty name+canonical now returns an explicit error
• add e2e coverage for name-only creation (project create, including --update, and env create)

Validation

• PATH="$HOME/go/bin:$PATH" GOTOOLCHAIN=go1.25.0 make lint
• PATH="$HOME/go/bin:$PATH" GOTOOLCHAIN=go1.25.0 go test ./cmd/cycloid/projects ./cmd/cycloid/environments ./internal/cyargs
• PATH="$HOME/go/bin:$PATH" GOTOOLCHAIN=go1.25.0 go test -c ./cmd/cycloid/middleware
• PATH="$HOME/go/bin:$PATH" GOTOOLCHAIN=go1.25.0 go test -c ./e2e

Notes

• running middleware/e2e tests directly requires backend/license test configuration; compile checks were run for those packages in this environment.

Linear Issue: CLI-110