feat: entropy profile temporal validation for anomaly detection

[AKIB473]

Implements temporal validation of entropy profiles. Detects frozen (emulator) and noisy (spoofing) profiles. Wallet: miner-20260508-rustchain

[github-actions]

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[fengqiankun6-sudo]

PR #4175 Review: Entropy Profile Temporal Validation

Overall: ✅ LGTM — Good anomaly detection implementation

Analysis

What it does:

• Tracks last 10 fingerprint snapshots per miner
• Implements temporal consistency validation to detect:
  • "Frozen" profiles (zero variance → emulator detection)
  • "Noisy" profiles (random spoofing detection)
• Integration with reward calculation

Strengths:

• Clear docstrings explaining the threat model
• Good variance threshold logic
• Proper dataclass structure for snapshots
• Integration test coverage

Issues:

1. ⚠️ Snapshot size limit: Only stores 10 snapshots in memory — if a miner generates many fingerprints between reward calculations, older snapshots get dropped. Consider persisting or increasing the window.

2. ⚠️ No upper bound on variance check: The "noisy" profile detection has a lower bound (variance > 0.01) but what about an upper bound? Some hardware genuinely has high variance. Consider adding a sanity cap.

3. ⚠️ datetime.now() in validate function: Calling datetime.now() inside the validation loop could cause issues with batch processing. Pass timestamp as argument for testability.

Minor:

• README_ENTROPY.md is a good addition
• The entropy calculation (hashlib.sha256 on fingerprint bytes) is solid

Good work.

[fengqiankun6-sudo]

Review: Entropy Profile Temporal Validation ✅

Assessment: LGTM — Solid security enhancement for emulator/spoofing detection.

Strengths:

• Clean 2-file change, focused implementation
• Good separation of freeze vs noise detection
• Uses existing dataclass properly

Minor Notes:

• Consider documenting the thresholds for and as constants
• The detection logic looks correct for catching both attack vectors

Approved. Ship it! 🚀