AWS Bedrock, Google Vertex AI, and Three-Tier Model Support

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Shannon now supports AWS Bedrock and Google Vertex AI as alternative model providers, alongside direct Anthropic API access.

We've also introduced a three-tier model system that assigns the right model to each agent based on task complexity:

• Large (e.g., Opus) — Pre-recon and deep source code analysis
• Medium (e.g., Sonnet) — Most agents including vulnerability analysis and exploitation
• Small (e.g., Haiku) — Report summarization

You can override each tier independently via environment variables:

ANTHROPIC_SMALL_MODEL=...
ANTHROPIC_MEDIUM_MODEL=...
ANTHROPIC_LARGE_MODEL=...

This applies across all providers. See the AWS Bedrock and Google Vertex AI setup instructions in the README.