docs: dev --env-file help/docs say it does not reach tasks, but it does #4425

Provide environment information

trigger.dev 4.5.0 (also verified 4.5.9)

Describe the bug

The --env-file option is documented — in the CLI --help for dev/deploy/preview and in the docs pages (cli-dev-commands, cli-deploy-commands, cli-preview-archive) — as:

Load environment variables from a file. This will only hydrate the process.env of the CLI process, not the tasks.

But in dev, the file is passed through to the tasks. DevSupervisor.#getEnvVars() (dev/devSupervisor.ts) builds the run environment from resolveLocalEnvVars(this.options.args.envFile, …):

async #getEnvVars() {
    const environmentVariablesResponse = await this.options.client.getEnvironmentVariables(...);
    return {
        ...resolveLocalEnvVars(this.options.args.envFile, environmentVariablesResponse.success ? ... : {}),
        NODE_ENV: "development",
        ...
    };
}

and resolveLocalEnvVars(envFile, …) → resolveDotEnvVars(undefined, envFile) reads exactly that file and includes it in what the task receives via process.env.

To reproduce

1. echo "PROBE=from-file" > custom.env
2. trigger dev --env-file custom.env
3. In a task: process.env.PROBE
4. It is from-file — the task does see the --env-file value.

Expected per the docs: the task should NOT see it (docs say the flag only affects the CLI process).

Which is correct?

The behavior (file reaches tasks) is arguably the more useful one — passing --env-file /path/to/empty is a clean way to make the CLI read no ambient .env* files and rely solely on the injected process.env. But the docs and --help text state the opposite, so please either:

• fix the docs/--help to say --env-file values are included in the task environment, or
• if the documented behavior is the intended contract, fix dev to not pass envFile into resolveLocalEnvVars.

Either way the code and the docs currently disagree, which makes --env-file hard to reason about.

Additional information

Related: #2999 (the .env vs .env.local precedence bug in the same resolveDotEnvVars path).