Add folder anatomy (scripts/agent.py + references/api-reference.md) for 648 cybersecurity skills

Complete skill folder anatomy across all cybersecurity skills:
- scripts/agent.py: 80-150 line Python agents using real libraries (impacket,
  boto3, azure-mgmt-*, kubernetes, pefile, yara, scapy, shodan, stix2, etc.)
- references/api-reference.md: real API documentation with method signatures
- LICENSE: MIT license for all skill folders

skills/implementing-api-threat-protection-with-apigee/references/api-reference.md

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+# API Reference: Implementing API Threat Protection with Apigee
+
+## JSONThreatProtection Policy
+
+```xml
+<JSONThreatProtection name="JSON-Threat">
+    <ObjectEntryCount>25</ObjectEntryCount>
+    <ArrayElementCount>100</ArrayElementCount>
+    <ContainerDepth>5</ContainerDepth>
+    <StringValueLength>500</StringValueLength>
+    <Source>request</Source>
+</JSONThreatProtection>
+```
+
+## SpikeArrest Policy
+
+```xml
+<SpikeArrest name="Spike-Arrest">
+    <Rate>30ps</Rate>
+    <Identifier ref="request.header.x-api-key"/>
+</SpikeArrest>
+```
+
+## RegularExpressionProtection
+
+```xml
+<RegularExpressionProtection name="Regex-Protect">
+    <Source>request</Source>
+    <QueryParam name="*">
+        <Pattern>[\s]*((delete)|(exec)|(drop\s*table))</Pattern>
+    </QueryParam>
+</RegularExpressionProtection>
+```
+
+## Apigee Management API
+
+```bash
+# Deploy proxy revision
+curl -X POST "https://apigee.googleapis.com/v1/organizations/{org}/environments/{env}/apis/{api}/revisions/{rev}/deployments" \
+  -H "Authorization: Bearer $(gcloud auth print-access-token)"
+
+# List deployed proxies
+curl "https://apigee.googleapis.com/v1/organizations/{org}/apis" \
+  -H "Authorization: Bearer $(gcloud auth print-access-token)"
+```
+
+## Recommended Policy Limits
+
+| Setting | Recommended | Description |
+|---------|-------------|-------------|
+| ContainerDepth | 5 | JSON nesting depth |
+| StringValueLength | 500 | Max string value |
+| ObjectEntryCount | 25 | Max object keys |
+| SpikeArrest Rate | 30ps | Requests per second |
+
+### References
+
+- Apigee Policies: https://cloud.google.com/apigee/docs/api-platform/reference/policies
+- Apigee Security: https://cloud.google.com/apigee/docs/api-platform/security