chore: add version management and changelog

- Add pyproject.toml with project metadata and version (1.1.0)
- Update config.py to read version from pyproject.toml
- Update main.py to use centralized version in FastAPI app
- Add CHANGELOG.md documenting v1.0.0 and v1.1.0 changes

Version is now the single source of truth in pyproject.toml and is
displayed in the health check endpoint and API docs.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pyproject.toml

@@ -0,0 +1,31 @@
+[project]
+name = "library-desk"
+version = "1.1.0"
+description = "Coordination service for The Library system - HybridRAG queries, document ingestion, entity extraction, and knowledge consolidation"
+readme = "README.md"
+requires-python = ">=3.12"
+license = {text = "MIT"}
+authors = [
+    {name = "JP Schweitzer"}
+]
+keywords = ["rag", "knowledge-graph", "wiki", "semantic-search", "neo4j", "qdrant"]
+classifiers = [
+    "Development Status :: 4 - Beta",
+    "Framework :: FastAPI",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: MIT License",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.12",
+]
+
+[project.urls]
+Homepage = "https://github.com/jpmschweitzer/library-desk"
+Documentation = "https://github.com/jpmschweitzer/library-desk#readme"
+
+[build-system]
+requires = ["setuptools>=61.0"]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools.packages.find]
+where = ["."]
+include = ["src*"]