Description

Add support for --json flag across all CLI commands to enable machine-readable output for scripting and automation use cases.

Related Issue

N/A

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Other (please describe):

Changes Made

• Add global --json flag to the CLI entry point with a preAction hook to set JSON mode
• Create new src/cli/utils/json.ts with utilities: setJsonMode(), isJsonMode(), outputJson(), outputJsonError()
• Make RunCommandResult<TData> generic to support typed JSON output data
• Update all commands to return structured data for JSON output:
  • whoami: returns { email, name }
  • entities push: returns { created, updated, deleted }
  • functions deploy: returns { deployed, errors }
  • project create: returns { name, id, root, dashboardUrl }
  • project dashboard: returns { dashboardUrl }
  • project link: returns { projectId, dashboardUrl }
  • site deploy: returns { appUrl } or { cancelled: true }
• Commands that don't support JSON (login, logout) use RunCommandResult<never>
• Suppress log.* calls and spinners in JSON mode via isJsonMode() checks
• Auto-confirm prompts in JSON mode for non-destructive actions (e.g., site deploy)
• Update AGENTS.md with comprehensive JSON output documentation and guidelines

Testing

• I have tested these changes locally
• I have added/updated tests as needed
• All tests pass (npm test)

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (if applicable)
• My changes generate no new warnings
• I have updated AGENTS.md if I made architectural changes

Additional Notes

JSON Output Structure

Success responses (stdout):

{
  "success": true,
  "data": { /* command-specific data */ }
}

Error responses (stderr):

{
  "success": false,
  "error": {
    "message": "Error description",
    "code": "ERROR_CODE"
  }
}

Exceptions

• login and logout do not support --json as they are user-facing authentication commands that require interactive browser flow