Add local error logging for CLI diagnostics

[Copilot]

Open-source CLI tools need diagnostic data without sacrificing user privacy. Cloud services like Datadog are inappropriate for this use case.

Implementation

• Error logger (src/utils/error-logger.ts)

  • Local file-based logging to ~/.tsu/logs/errors.log
  • Automatic sanitization: home paths → ~, secrets → [REDACTED]
  • Enabled by default, opt-out via TSU_ERROR_LOG=false
  • Captures: timestamp, versions, platform, command, error, stack trace

• Integration

  • Updated git root, git changed commands
  • Enhanced ensureCondition helper with optional logging
  • Exported utilities for library consumers

• Documentation

  • User guide: configuration, viewing logs, reporting issues
  • Security: privacy guarantees, data sanitization details
  • Contributing: integration patterns for new commands

Usage

import { logError } from '../utils/error-logger.js';

export function myCommand() {
  try {
    // Command logic
  } catch (error) {
    logError(error as Error, 'tsu my command');
    console.error('Error: Something went wrong');
    process.exit(1);
  }
}

# Disable logging
TSU_ERROR_LOG=false tsu git changed

# View logs
cat ~/.tsu/logs/errors.log

Design Rationale

Local-only logging for open-source CLI:

• No external dependencies, API keys, or accounts
• Data never leaves user's machine
• Zero cost, works offline
• User can inspect/delete logs anytime
• Trade-off: manual aggregation vs automatic privacy

Warning

GitHub's Secret Scanning detected potential secrets in the added content. We attempted to remediate the issue by updating the code or redacting.

Original prompt

I think datadog as a webapp maybe isn't a good solution for my project. What would be a good way of logging when users experience errors etc for an open source cli program

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