Secure Credential Management System

[hddevteam]

Goal: Implement secure storage and management of API credentials within the browser extension.

Priority: High
Effort: Medium

Acceptance Criteria:

• Encrypted local storage for API keys
• Secure credential input interface
• API key validation and testing
• Environment-based configuration support
• No credentials stored in plain text

Technical Tasks:

• Implement encryption for credential storage
• Create secure credential input UI
• Add API key validation functions
• Implement connection testing functionality
• Create credential management interface

Related Epic: #1