Watch/subscribe commands output pretty-printed JSON errors instead of NDJSON

[localrivet]

Problem

The gmail +watch and events +subscribe commands output NDJSON for normal events, but when an error occurs (e.g., 401 auth failure), the error JSON is pretty-printed across multiple lines:

{
  "error": {
    "code": 401,
    "message": "Failed to get Pub/Sub token: Failed to get token",
    "reason": "authError"
  }
}

Consumers that parse stdout line-by-line (the expected NDJSON protocol) get individual lines like {, "error": {, "code": 401, — none of which are valid JSON.

Expected

Errors should be emitted as single-line NDJSON, matching the protocol used for normal events:

{"error":{"code":401,"message":"Failed to get Pub/Sub token: Failed to get token","reason":"authError"}}

Impact

This breaks any automation that consumes the NDJSON stream — the parser sees malformed lines and discards the error. The consumer has no idea the watch process is failing.

Version

gws 0.22.5

Reproduction

# Expire or revoke OAuth tokens, then:
gws gmail +watch --project my-project
# Error output is pretty-printed, not NDJSON

Suggested Fix

Use compact JSON serialization (serde_json::to_string instead of serde_json::to_string_pretty, or the equivalent) for all stdout output in watch/subscribe commands — both events and errors.

Alternatively, errors could go to stderr (where they arguably belong), but that would be a protocol change. The minimal fix is just compact JSON on stdout.

[localrivet]

Found the exact location after pulling the source:

File: crates/google-workspace-cli/src/error.rs:68-71

pub fn print_error_json(err: &GwsError) {
    let json = err.to_json();
    println!(
        "{}",
        serde_json::to_string_pretty(&json).unwrap_or_default()  // ← pretty-prints to stdout
    );

This is called from main() at line 57:

if let Err(err) = run().await {
    print_error_json(&err);
    std::process::exit(err.exit_code());
}

When +watch or +subscribe crashes (e.g., auth token expired), the error propagates up via ? to main(), which calls print_error_json() → pretty-printed JSON on stdout → breaks NDJSON consumers.

Fix: Change to_string_pretty to to_string on line 70. The human-readable version is already printed to stderr on lines 96-100.

There's also a secondary instance in watch.rs:468 where to_string_pretty is used for file output (which is fine), but the stdout path on line 486 correctly uses to_string. Similarly subscribe.rs:433 uses to_string_pretty for file output and to_string for stdout (line 453) — both correct.

So the only fix needed is the one line in error.rs:70.