Add version tracking via pyproject.toml

- Add pyproject.toml with project metadata and version 1.0.0
- Update config.py to load version from pyproject.toml
- Update Dockerfile to include pyproject.toml in build
- Add CHANGELOG.md documenting initial release
- Update build workflow registry to internal domain

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

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

src/config.py

@@ -1,9 +1,25 @@
 """
 Global configuration for Core Code API
 """
+import tomllib
+from pathlib import Path
 from pydantic_settings import BaseSettings
 from functools import lru_cache
 
+
+def _get_version_from_pyproject() -> str:
+    """Load version from pyproject.toml"""
+    pyproject_path = Path(__file__).parent.parent / "pyproject.toml"
+    try:
+        with open(pyproject_path, "rb") as f:
+            data = tomllib.load(f)
+            return data.get("project", {}).get("version", "0.0.0")
+    except FileNotFoundError:
+        return "0.0.0"
+
+
+__version__ = _get_version_from_pyproject()
+
 # Import infrastructure credentials from gitignored module
 try:
     from src.credentials import (
@@ -35,7 +51,7 @@ class Settings(BaseSettings):
 
     # Application
     app_name: str = "Core Code API"
-    app_version: str = "1.0.0"
+    app_version: str = __version__
     debug: bool = False
 
     # Server