Changes

PR #1540 by ksylvan: Add Langdock AI and enhance generic OpenAI compatible support

• Implement dynamic URL handling with environment variables for provider configuration
• Refactor ProviderMap to support URL templates with template variable parsing
• Extract and parse template variables from BaseURL with fallback to default values
• Add os and strings packages to imports for enhanced functionality
• Reorder providers for consistent key order in ProviderMap

Direct commits

• Improve Bedrock client error handling with wrapped errors and AWS region validation
• Add ai.Vendor interface implementation check for better compliance
• Fix resource cleanup in SendStream with proper nil checks for response parsing
• Update AWS credentials checking to include AWS_DEFAULT_REGION environment variable
• Update paper analyzer functionality