Add comprehensive unit tests for Claude Code mode:
- Test claudeProviderInitializer validation and capabilities
- Test header logic for beta=true query parameter
- Test buildClaudeTextGenRequest for standard and Claude Code modes
- Test system prompt injection when missing
- Test Bash tool injection when missing
- Test deduplication of existing system prompt and tools
- Test constants and GetApiName
Note: TransformRequestHeaders and TransformRequestBody tests are skipped
as they require WASM runtime. Core logic is tested indirectly through
buildClaudeTextGenRequest tests.
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