feat: Full code review, bug fixes, and philosophy book generation

This commit includes:
- A full code review and bug fixes for language drift, package loading, and CLI crashes.
- The generated 15,000-word philosophy manuscript.
- CODE_REVIEW.md and CHANGELOG.md documenting the process.

opus_orchestrator/agents/base.py

@@ -148,6 +148,9 @@ class BaseAgent(ABC, Generic[T]):
             Complete system prompt
         """
         base = self.system_prompt
+        
+        # Add universal language constraint
+        base += "\n\nIMPORTANT: You must respond ONLY in English. Do not use any other language."
 
         if context:
             context_str = "\n\n## Context\n"