cli crashes if no .env or empty .env file #795

Environment: MacOS Tahoe 26.3.1, M2 mbp, using zsh, brew and pip.
When I tried to create an app, cli crashes. I had two issues when it happened: 1) not in a true project, 2) no .env file. I fixed this, works now.

Requesting better user feedback for these two user errors.

(rtagent) ➜ ringtell lk app create
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x0 pc=0x10365c684]
goroutine 1 [running]:
main.setupTemplate({0x105d30e98, 0x1a059e389a10}, 0x105ede3e0)
github.com/livekit/livekit-cli/v2/cmd/lk/app.go:304 +0x544
github.com/urfave/cli/v3.(*Command).run(0x105ede3e0, {0x105d30e98, 0x1a059e389a10}, {0x1a059e7a5e10, 0x1, 0x1})
github.com/urfave/cli/v3@v3.4.1/command_run.go:344 +0x1e7c
github.com/urfave/cli/v3.(*Command).run(0x105ede160, {0x105d30e98, 0x1a059e3898f0}, {0x1a059e43e260, 0x2, 0x2})
github.com/urfave/cli/v3@v3.4.1/command_run.go:278 +0x1898
github.com/urfave/cli/v3.(*Command).run(0x1a059e154f08, {0x105d30e98, 0x1a059e2f0060}, {0x1a059e2224b0, 0x3, 0x3})
github.com/urfave/cli/v3@v3.4.1/command_run.go:278 +0x1898
github.com/urfave/cli/v3.(*Command).Run(...)
github.com/urfave/cli/v3@v3.4.1/command_run.go:94
main.main()
github.com/livekit/livekit-cli/v2/cmd/lk/main.go:92 +0xd0c
(rtagent) ➜ ringtell