fix(security): remove hardcoded password from agent protocols

- Replace hardcoded password with environment variables
- Add .env.example template for secure configuration
- Update .gitignore to prevent committing secrets
- Add os import for environment variable support

Fixes critical security vulnerability in agent message protocol

apps/agent-protocols/.env.example

@@ -0,0 +1,19 @@
+# AITBC Agent Protocols Environment Configuration
+# Copy this file to .env and update with your secure values
+
+# Agent Protocol Encryption Key (generate a strong, unique key)
+AITBC_AGENT_PROTOCOL_KEY=your-secure-encryption-key-here
+
+# Agent Protocol Salt (generate a unique salt value)
+AITBC_AGENT_PROTOCOL_SALT=your-unique-salt-value-here
+
+# Agent Registry Configuration
+AGENT_REGISTRY_HOST=0.0.0.0
+AGENT_REGISTRY_PORT=8003
+
+# Database Configuration
+AGENT_REGISTRY_DB_PATH=agent_registry.db
+
+# Security Settings
+AGENT_PROTOCOL_TIMEOUT=300
+AGENT_PROTOCOL_MAX_RETRIES=3