fix: suppress npm progress output in tests for hermeticity (fixes #2004)

[gavin913427-hash]

What does this PR do?

Makes integration tests hermetic by suppressing npm progress output that pollutes stdout and breaks assertions (fixes #2004)

Problem

Integration tests fail because some CLI commands trigger real npm dependency resolution during test execution. npm prints progress output (idealTree spinners, dependency logs) to stdout, which breaks tests that assert exact empty or fixed string output.

Solution

Added npm environment variables to test/helpers/init.js:

• npm_config_loglevel=silent — suppresses npm log output
• npm_config_progress=false — disables npm progress bars
• NPM_CONFIG_LOGLEVEL=silent — uppercase variant for broader compatibility
• NPM_CONFIG_PROGRESS=false — uppercase variant

This ensures all npm operations during tests run silently, preventing stdout pollution.

Why this approach

• Minimal change: Only 6 lines added to a single file
• No test rewrites needed: Existing assertions work as-is
• Environment-independent: Works regardless of npm version, OS, or network conditions
• Non-invasive: Doesn't affect the CLI's behavior in production

Related issue(s)

Fixes #2004

Checklist

• Added npm environment variables to test init
• Added changeset
• No changes to CLI behavior

[changeset-bot]

🦋 Changeset detected

Latest commit: 51af4c5

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@asyncapi/cli	Patch

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud