feat: Add --json flag for JSONL output mode (Issue #346)

[Tianlin0725]

Summary

Added --json flag to the RustChain miner that enables JSONL (JSON Lines) output format. This allows other tools and scripts to parse miner output programmatically.

Changes

• Added --json command line argument to rustchain_linux_miner.py
• Added emit() function that handles both human-readable and JSON output modes
• Key events now emit JSON objects:
  • startup: Wallet, node, serial info
  • fingerprint: Check status and results
  • attestation: Success/failure with details
  • balance: Current balance
  • mining: Start, progress, and stop events
  • cycle: Cycle number and timestamp

Example Usage

# Normal output (human-readable)
python3 rustchain_linux_miner.py --wallet test

# JSON output
python3 rustchain_linux_miner.py --wallet test --json
# Output:
# {"event": "startup", "wallet": "...", "node": "...", "serial": "..."}
# {"event": "fingerprint", "status": "running", "total_checks": 6}
# {"event": "fingerprint", "status": "passed", "checks_passed": 6, "checks_total": 6}

Benefits

• Enables integration with monitoring dashboards
• Allows automated alerting based on miner events
• Facilitates data analysis of mining patterns
• Supports integration with other tools and scripts

/claim #346

[github-actions]

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[sophiaeagent-beep]

Closing as duplicate — you submitted the same feature in #352 which is the better version. Please focus on #352.