Move blockchain app READMEs to centralized documentation

- Relocate blockchain-event-bridge README content to docs/apps/blockchain/blockchain-event-bridge.md
- Relocate blockchain-explorer README content to docs/apps/blockchain/blockchain-explorer.md
- Replace app READMEs with redirect notices pointing to new documentation location
- Consolidate documentation in central docs/ directory for better organization

docs/apps/plugins/plugin-security.md

@@ -0,0 +1,218 @@
+# Plugin Security
+
+## Status
+✅ Operational
+
+## Overview
+Security plugin for scanning, validating, and monitoring AITBC plugins for security vulnerabilities and compliance.
+
+## Architecture
+
+### Core Components
+- **Vulnerability Scanner**: Scans plugins for security vulnerabilities
+- **Code Analyzer**: Analyzes plugin code for security issues
+- **Dependency Checker**: Checks plugin dependencies for vulnerabilities
+- **Compliance Validator**: Validates plugin compliance with security standards
+- **Policy Engine**: Enforces security policies
+
+## Quick Start (End Users)
+
+### Prerequisites
+- Python 3.13+
+- Access to plugin files
+- Vulnerability database access
+
+### Installation
+```bash
+cd /opt/aitbc/apps/plugin-security
+.venv/bin/pip install -r requirements.txt
+```
+
+### Configuration
+Set environment variables in `.env`:
+```bash
+VULN_DB_URL=https://vuln-db.example.com
+SCAN_DEPTH=full
+COMPLIANCE_STANDARDS=OWASP,SANS
+POLICY_FILE=/path/to/policies.yaml
+```
+
+### Running the Service
+```bash
+.venv/bin/python main.py
+```
+
+## Developer Guide
+
+### Development Setup
+1. Clone the repository
+2. Create virtual environment: `python -m venv .venv`
+3. Install dependencies: `pip install -r requirements.txt`
+4. Configure vulnerability database
+5. Configure security policies
+6. Run tests: `pytest tests/`
+
+### Project Structure
+```
+plugin-security/
+├── src/
+│   ├── vulnerability_scanner/ # Vulnerability scanning
+│   ├── code_analyzer/        # Code analysis
+│   ├── dependency_checker/   # Dependency checking
+│   ├── compliance_validator/ # Compliance validation
+│   └── policy_engine/       # Policy enforcement
+├── policies/                # Security policies
+├── tests/                   # Test suite
+└── pyproject.toml           # Project configuration
+```
+
+### Testing
+```bash
+# Run all tests
+pytest tests/
+
+# Run vulnerability scanner tests
+pytest tests/test_scanner.py
+
+# Run compliance validator tests
+pytest tests/test_compliance.py
+```
+
+## API Reference
+
+### Vulnerability Scanning
+
+#### Scan Plugin
+```http
+POST /api/v1/security/scan
+Content-Type: application/json
+
+{
+  "plugin_id": "string",
+  "version": "1.0.0",
+  "scan_depth": "quick|full",
+  "scan_types": ["code", "dependencies", "configuration"]
+}
+```
+
+#### Get Scan Results
+```http
+GET /api/v1/security/scan/{scan_id}
+```
+
+#### Get Scan History
+```http
+GET /api/v1/security/scan/history?plugin_id=string
+```
+
+### Code Analysis
+
+#### Analyze Code
+```http
+POST /api/v1/security/analyze
+Content-Type: application/json
+
+{
+  "plugin_id": "string",
+  "code_path": "/path/to/code",
+  "analysis_types": ["sast", "secrets", "quality"]
+}
+```
+
+#### Get Analysis Report
+```http
+GET /api/v1/security/analyze/{analysis_id}
+```
+
+### Dependency Checking
+
+#### Check Dependencies
+```http
+POST /api/v1/security/dependencies/check
+Content-Type: application/json
+
+{
+  "plugin_id": "string",
+  "dependencies": [{"name": "string", "version": "string"}]
+}
+```
+
+#### Get Vulnerability Report
+```http
+GET /api/v1/security/dependencies/vulnerabilities?plugin_id=string
+```
+
+### Compliance Validation
+
+#### Validate Compliance
+```http
+POST /api/v1/security/compliance/validate
+Content-Type: application/json
+
+{
+  "plugin_id": "string",
+  "standards": ["OWASP", "SANS"],
+  "severity": "high|medium|low"
+}
+```
+
+#### Get Compliance Report
+```http
+GET /api/v1/security/compliance/report/{validation_id}
+```
+
+### Policy Enforcement
+
+#### Check Policy Compliance
+```http
+POST /api/v1/security/policies/check
+Content-Type: application/json
+
+{
+  "plugin_id": "string",
+  "policy_name": "string"
+}
+```
+
+#### List Policies
+```http
+GET /api/v1/security/policies
+```
+
+## Configuration
+
+### Environment Variables
+- `VULN_DB_URL`: Vulnerability database URL
+- `SCAN_DEPTH`: Default scan depth (quick/full)
+- `COMPLIANCE_STANDARDS`: Compliance standards to enforce
+- `POLICY_FILE`: Path to security policies file
+
+### Scan Types
+- **SAST**: Static Application Security Testing
+- **Secrets Detection**: Detect hardcoded secrets
+- **Dependency Scanning**: Scan dependencies for vulnerabilities
+- **Configuration Analysis**: Analyze configuration files
+
+### Compliance Standards
+- **OWASP**: OWASP security standards
+- **SANS**: SANS security controls
+- **CIS**: CIS benchmarks
+
+## Troubleshooting
+
+**Scan not running**: Check vulnerability database connectivity and plugin accessibility.
+
+**False positives**: Review scan rules and adjust severity thresholds.
+
+**Compliance validation failed**: Review plugin code against compliance standards.
+
+**Policy check failed**: Verify policy configuration and plugin compliance.
+
+## Security Notes
+
+- Regularly update vulnerability database
+- Use isolated environment for scanning
+- Implement rate limiting for scan requests
+- Secure scan results storage
+- Regularly audit security policies
+- Monitor for security incidents