Update Python version requirements and fix compatibility issues

- Bump minimum Python version from 3.11 to 3.13 across all apps
- Add Python 3.11-3.13 test matrix to CLI workflow
- Document Python 3.11+ requirement in .env.example
- Fix Starlette Broadcast removal with in-process fallback implementation
- Add _InProcessBroadcast class for tests when Starlette Broadcast is unavailable
- Refactor API key validators to read live settings instead of cached values
- Update database models with explicit

packages/solidity/aitbc-token/cache/solidity-files-cache.json

@@ -123,6 +123,42 @@
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     "/home/oib/windsurf/aitbc/packages/solidity/aitbc-token/node_modules/@openzeppelin/contracts/utils/cryptography/MessageHashUtils.sol": {
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@@ -161,42 +197,6 @@
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