Please don't remove pulumi env run [environment] shorthand

[EvanBoyle]

I recently noticed this deprecation message after updating from an older version of the CLI:

$ pulumi env run ai-dev pnpm dev 
Warning: Referring to an environment name ('ai-dev') without a project is deprecated.
Please use 'cortexclick/default/ai-dev' or 'default/ai-dev' instead.

I don't make use of the project structure (everything is in default) and I am really not excited about having to type out default/[env] every time I want to invoke the CLI. It just feels like an unnecessary inconvenience.

Today pulumi env run [environment] is just an alias to default-org/default/environment which is unambiguous.

This code even suggests that it is unambiguous and that this format is marked as "legacy":

esc/cmd/esc/cli/env.go

Lines 113 to 125 in e9e5988

	hasAmbiguousPath := false
	orgName = cmd.esc.account.DefaultOrg
	projectName = client.DefaultProject
	isUsingLegacyID := false
	parts := strings.Split(refStr, "/")
	switch l := len(parts); {
	case l == 1:
	// <environment-name>
	envNameAndVersion = parts[0]
	isUsingLegacyID = true

I'd love to get a clear picture of why this had to be marked as legacy and removed. I tried digging through some PRs, but I couldn't really find anything in issues or PR descriptions that outlined the rationale for the change. Closest thing I found was this PR comment:

#369 (comment)

My closest guess is that you all don't want people accidentally creating envs in the default project, or unexpectedly opening a env that exists in both default and another project. I can understand that, but I am not at the scale where I need or care about projects. I just don't want to unnecessarily type stuff every time - especially if there isn't a problem with ambiguity and the goal is to just protect me from myself.

Is there a happy medium here? Maybe support could be added for $PULUMI_ESC_DEFAULT_PROJECT so that the short commands can be kept?