chore: Bump version to 6.0.0 for attune-ai release

Major version bump reflects the package rename:
- empathy-framework → attune-ai
- empathy_os → attune

This is a breaking change requiring users to update imports.

Author: silversurfer562

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "attune-ai"
-version = "5.3.0"
+version = "6.0.0"
 description = "AI collaboration framework with real LLM agent execution, AskUserQuestion tool integration, Socratic agent generation, progressive tier escalation (70-85% cost savings), meta-orchestration, dynamic agent composition (10 patterns including Anthropic-inspired), intelligent caching (85% hit rate), semantic workflow discovery, visual workflow editor, MCP integration for Claude Code, and multi-agent orchestration."
 readme = {file = "README.md", content-type = "text/markdown"}
 requires-python = ">=3.10"