Complete folder anatomy for all 649 cybersecurity skills + update LICENSE to Mahipal

- Add scripts/agent.py and references/api-reference.md to all remaining skills
- Update all 648 LICENSE files: copyright now reads 'Mahipal'
- Add implementing-security-monitoring-with-datadog (new skill with full anatomy)
- All 649 skills now have: SKILL.md, LICENSE, scripts/agent.py, references/api-reference.md

skills/hunting-for-data-exfiltration-indicators/references/api-reference.md

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+# API Reference: Data Exfiltration Detection
+
+## Exfiltration Methods (MITRE ATT&CK)
+
+| Technique | ID | Description |
+|-----------|----|-------------|
+| Exfiltration Over C2 Channel | T1041 | Via existing C2 |
+| Exfiltration Over Alternative Protocol | T1048 | DNS, ICMP, etc. |
+| Exfiltration Over Web Service | T1567 | Cloud storage |
+| Automated Exfiltration | T1020 | Scripted transfer |
+
+## DNS Exfiltration Indicators
+
+| Indicator | Threshold |
+|-----------|-----------|
+| Shannon entropy | > 3.5 |
+| Subdomain length | > 40 chars |
+| Query volume per domain | > 100/hour |
+| TXT record responses | > 500 bytes |
+
+## Zeek Log Fields
+
+### conn.log
+| Field | Description |
+|-------|-------------|
+| `ts` | Timestamp |
+| `id.orig_h` | Source IP |
+| `id.resp_h` | Destination IP |
+| `orig_bytes` | Bytes from source |
+| `resp_bytes` | Bytes from destination |
+
+### dns.log
+| Field | Description |
+|-------|-------------|
+| `query` | DNS query name |
+| `qtype_name` | Query type (A, TXT, etc.) |
+| `answers` | Response answers |
+
+## Python Libraries
+
+| Library | Use |
+|---------|-----|
+| `csv` | Parse Zeek TSV logs |
+| `math` | Shannon entropy calculation |
+| `collections.defaultdict` | Aggregate statistics |
+| `dpkt` | PCAP parsing |
+| `scapy` | Packet-level analysis |
+
+## Shannon Entropy Formula
+
+```
+H(X) = -sum(p(x) * log2(p(x)))
+```
+Normal domain: H < 3.0, Exfil encoded: H > 3.5